Device or apparatus for manipulating matter

ABSTRACT

The present invention accordingly provides a device or apparatus for manipulating matter in a confined or inaccessible space, comprising manipulator means at least partly constructed of one or more bent or twisted elongate shape memory alloy members having pseudoelasticity at the intended manipulation temperature, and a hollow housing (preferably of elongate tubular form) or cannula capable of holding at least the shape memory alloy member(s) in a relatively straightened state, and actuating means for extending the shape memory alloy member(s) from the housing to manipulate matter within the said space and for withdrawing the shape memory alloy member(s) into the housing, the arrangement being such that the shape-memory alloy member(s) bend(s) or twist(s) pseudoelastically in a lateral or helical sense to manipulate the matter on extending from the housing at the said manipulation temperature, and become(s) relatively straightened on withdrawal into the housing at the said temperature. 
     Preferably the invention provides such a device or apparatus which is of elongate form for surgical manipulation of matter within a living body, and which has the manipulator means at its distal end with the shape memory alloy member(s) having pseudoelasticity at the temperature to be encountered within that body, and wherein the actuating means is operable from the proximal end of the device.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation-in-part application of U.S.applications Ser. Nos. 07/594,768 filed Oct. 9, 1990; 07/608,117 filedNov. 1, 1990; 07/594,769 filed Oct. 9, 1990; 07/608,121 filed Nov. 11,1990; 07/594,871 filed Oct. 9, 1990; 07/594,896 filed Oct. 9, 1990;07/594,874 filed Oct. 9, 1990; 07/594,873 filed Oct. 9, 1990; and07/656,651 filed Feb. 15, 1991 all abandoned. The entire disclosures ofthese applications are hereby incorporated by reference for allpurposes.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a device or apparatus for manipulating matterwithin a confined or inaccessible space, especially during surgery in aliving body.

2. Description of the Prior Art

Matter may be manipulated in such circumstances in various ways, forexample by application of a ligature, by suturing, by cutting with aknife or scissor action, or by capture and retrieval in devices such asscreens, baskets, barriers, pouches, or retractors. Such manipulationmay be difficult when operating in the confined space of a very deepwound or through a small arthroscopic or other endoscopic incision orbody aperture.

Many forms of apparatus for performing surgical operations have beenproposed previously using flexible steel wires which spring apart whenextended from the distal end of a tube and which can be brought togetheragain on withdrawal back into the tube. Examples of such known devicesmay be seen in U.S. Pat. Nos. 2,114,695, 2,137,710, 2,670,519,3,404,677, 4,174,715, 4,190,042, 4,222,380, 4,249,533, 4,347,846,4,655,219, 4,691,705, 4,741,335, 4,768,505 and 4,909,789. However, thesedevices may not be completely satisfactory for various reasons,especially after repeated use or long storage which may fatigue thematerials used.

Attempts have been made to use shape memory metals in surgicalapparatus, but these suffer from inconvenience and from the risk ofdamage to living tissues resulting from the need either to cool thememory metal while positioning it in the body so that body heatthereafter actuates the shape memory effect, or to heat the metal abovebody temperature to actuate it after positioning. Examples of suchattempts are described in U.S. Pat. Nos. 4,509,517, 3,868,956 and4,425,908.

SUMMARY OF THE INVENTION

The present invention uses pseudoelastic materials, preferablypseudoelastic shape memory alloys, which bend pseudoelastically toperform manipulations which may be difficult or impossible to achievereliably with previously known devices. Pseudoelastic alloys havepreviously been described for non-manipulative devices such as lesionmarker probes, bone anchors, heart valves, intrauterine devices, dentalarch wire, coil stents and filters, as described in U.S. Pat. Nos.4,665,906 (Jervis), 4,616,656 (Nicholson), 4,898,156 (Gatturna),4,899,743 (Nicholson), and 4,946,468 (Li). In one case, U.S. Pat. No.4,926,860 (Stice) describes a straight suturing needle made of suchalloy which ensures the needle emerges straight after being insertedthrough a curved cannula. None of these known uses in any way suggeststhe present ingenious use of the power of pseudoelastic bending onextending a pseudoelastic manipulator means from a cannula to performmanipulations in difficult locations.

The present invention accordingly provides a device or apparatus formanipulating matter in a confined or inaccessible space, comprising

(i) manipulator means at least partly constructed of one or more bent ortwisted elongate shape memory alloy members having pseudoelasticity atthe intended manipulation temperature, and

(ii) a hollow housing (preferably of elongate tubular form) or cannulacapable of holding at least the shape memory alloy member(s) in arelatively straightened state, and

(iii) actuating means for extending the shape memory alloy member(s)from the housing to manipulate matter within the said space and forwithdrawing the shape memory alloy member(s) into the housing, thearrangement being such that the shape-memory alloy member(s) bend(s) ortwist(s) pseudoelastically in a lateral or helical sense to manipulatethe matter on extending from the housing at the said manipulationtemperature, and become(s) relatively straightened on withdrawal intothe housing at the said temperature.

Preferably the invention provides such a device or apparatus which is ofelongate form for surgical manipulation of matter within a living body,and which has the manipulator means at its distal end with the shapememory alloy member(s) having pseudoelasticity at the temperature to beencountered within that body, and wherein the actuating means isoperable from the proximal end of the device.

Various forms of device or apparatus will now be describedindependently, it being understood that all may be inventive inthemselves, although all are preferably within the scope of at least thefirst (more preferably both) of the two immediately precedingparagraphs. Non-surgical uses may be appropriate for some forms.

Any elastic material may be used in some of the embodiments of thisinvention, but it is generally preferred to use a pseudoelasticmaterial. Many different materials exhibit pseudoelasticity and can beused in any embodiment of this invention. It is preferred to use apseudoelastic shape memory alloy.

The term "elastic material" is used herein to mean a material that hasspring-like properties, that is, it is capable of being deformed by anapplied stress and then springing back, or recovering, to or toward itsoriginal unstressed shape or configuration when the stress is removed.The elastic material is preferably highly elastic. The material can bepolymeric or metallic, or a combination of both. The use of metals, suchas shape memory alloys, is preferred. Shape memory alloys that exhibitpseudoelasticity, in particular superelasticity, are especiallypreferred. The elastic materials herein exhibit greater than 1% elasticdeformation, more generally greater than 2% elastic deformation.Preferably, the elastic materials herein exhibit greater than 4% elasticdeformation, more preferably greater than 6% elastic deformation.

Preferably, the elastic member is at least partially formed from apseudoelastic material, such as a shape memory alloy that exhibitspseudoelasticity. Shape memory alloys which exhibit superelasticity(also referred to in the literature as non-linear pseudoelasticity), areespecially preferred.

U.S. Pat. No. 4,935,068 to Duerig, which is commonly assigned with thepresent application and incorporated herein by reference, teaches thefundamental principles of shape memory alloys. Some alloys which arecapable of transforming between martensitic and austenitic phases areable to exhibit a shape memory effect. The transformation between phasesmay be caused by a change in temperature. For example, a shape memoryalloy in the martensitic phase will begin to transform to the austeniticphase when its temperature rises above A_(s) and the transformation willbe complete when the temperature rises above A_(f). The forwardtransformation will begin when the temperature drops below M_(s) andwill be complete when the temperature drops below M_(f). Thetemperatures M_(s), M_(f), A_(s), and A_(f) define the thermaltransformation hysteresis loop of the shape memory alloy.

Under certain conditions, shape memory alloys exhibit pseudoelasticity,which does not rely on temperature change in order to accomplish shapechange. A pseudoelastic alloy is capable of being elastically deformedfar beyond the elastic limits of conventional metals.

The property of pseudoelasticity of certain shape memory alloys, whichpreferably is used in the devices of this invention, is the subject of apaper entitled "An Engineer's Perspective of Pseudoelasticity", by T. W.Duerig and R. Zadno, published in Engineering Aspects of Shape MemoryAlloys, page 380, T. W. Duerig, K. Melton, D. Stoeckel, and M. Wayman,editors, Butterworth Publishers, 1990 (proceedings of a conferenceentitled "Engineering Aspects of Shape Memory Alloys", held in Lansing,Mich. in August 1988). As discussed in the paper, the disclosure ofwhich is incorporated herein by reference, certain alloys are capable ofexhibiting pseudoelasticity of two types.

"Superelasticity" arises in appropriately treated alloys while they arein their austenitic phase at a temperature which is greater than A_(s)and less than M_(d) (A_(s) is the temperature at which, when a shapememory alloy in its martensitic phase is heated, the transformation tothe austenitic phase begins, and M_(d) is the maximum temperature atwhich the transformation to the martensitic phase can be induced by theapplication of stress). Superelasticity can be achieved when the alloyis annealed at a temperature which is less than the temperature at whichthe alloy is fully recrystallized. Alternative methods of creatingsuperelasticity in shape memory alloys, such as solution treating andaging, or alloying, are also discussed in "An Engineer's Perspective ofPseudoelasticity", referenced above. An article may be provided with adesired configuration by holding it in that configuration duringannealing, or during solution treatment and aging. An article formedfrom an alloy which exhibits superelasticity can be deformedsubstantially reversibly by 11% or more. In contrast, "linearpseudoelasticity", is believed not to be accompanied by a phase change.It is exhibited by shape memory alloys which have been cold worked orirradiated to stabilize the martensite, but have not been annealed inthe manner discussed above. An article formed from an alloy whichexhibits linear pseudoelasticity can be deformed substantiallyreversibly by 4% or more. The treatment of shape memory alloys toenhance their pseudoelastic properties is also discussed inabove-mentioned U.S. Pat. No. 4,935,068 to Duerig, incorporated hereinby reference.

While the alloy that is used in the devices of this invention mayexhibit either linear pseudoelasticity or superelasticity (which issometimes referred to as non-linear pseudoelasticity), orpseudoelasticity of an intermediate type, it is generally preferred thatit exhibit superelasticity because of the large amount of deformationthat is available without the onset of plasticity. U.S. Pat. No.4,665,906 to Jervis, which is commonly assigned with the presentapplication and is incorporated herein by reference, teaches the use ofpseudoelastic shape memory alloys in medical devices.

The pseudoelastic material will be selected according to thecharacteristics desired of the article. When a shape memory alloy isused, it is preferably a nickel titanium based alloy, which may includeadditional elements which might affect the yield strength that isavailable from the alloy or the temperature at which particular desiredpseudoelastic characteristics are obtained. For example, the alloy maybe a binary alloy consisting essentially of nickel and titanium, forexample 50.8 atomic percent nickel and 49.2 atomic percent titanium, orit may include a quantity of a third element such as copper, cobalt,vanadium, chromium or iron. Alloys consisting essentially of nickel,titanium and vanadium, such as disclosed in U.S. Pat. No. 4,505,767, thedisclosure of which is incorporated herein by reference, are preferredfor some applications, particularly since they can also exhibitsuperelastic properties at or around body temperatures, and because theyare stiffer and/or can store more elastic energy. Copper based alloysmay also be used, for example alloys consisting essentially of copper,aluminum and nickel; copper, aluminum and zinc; and copper and zinc.

An article exhibiting superelasticity can be substantially reversiblydeformed, by as much as eleven percent or more. For example, a 1.00meter length of superelastic wire may be stretched to 1.11 meters inlength, wherein its alloy will undergo a phase change to at least apartially more martensitic phase known as stress-induced-martensite.Upon release of the stress, the wire will return substantially to its1.00 meter length, and its alloy will, correspondingly, return at leastsubstantially toward its more austenitic phase. By way of contrast, asimilar wire of spring steel or other conventional metal may only beelastically stretched approximately one percent, or to 1.01 meter inlength. Any further stretching of the conventional wire, if notresulting in actual breakage of the wire, will result in a non-elastic(plastic) transformation such that, upon relief of the stress, the wirewill not return to its original length. Linear pseudoelastic andsuperelastic materials may also be bent, twisted, and compressed, ratherthan stretched, to a far greater degree than conventional metals.

It is believed that the superelastic property is achieved by phasetransformation within the alloy, rather than by the dislocationmovements which occur during the plastic deformation of ordinary metals.A superelastic material may be deformed and released thousands of times,without being subject to breakage due to the metal fatigue which limitsthe number of deformation cycles which an ordinary metal may undergowithout failure.

Shape memory alloys have a special feature which is beneficial forcertain of the embodiments of this invention. As a superelastic shapememory alloy is increasingly deformed from its unconstrained shape, someof its austenitic phase changes into stress-induced-martensite. Thestress/strain curve presents a plateau during this phase change. Thismeans that while the alloy undergoes this phase change, it can deformgreatly with only minimal increases in loading. Therefore, elementscomprising superelastic shape memory alloys have a built-in safetyfeature. These elements can be designed (using appropriately treatedalloys and appropriate dimensions) such that when they are loaded beyonda certain amount, the elements will tend to deform with a concomitantaustenite to stress-induced-martensite phase change, instead of merelypresenting a greater resistance or force with limited deformation to theload, which is seen with conventional metals.

Just as the stress strain curves of shape memory alloys present aplateau upon loading, they also present a plateau in the stress straincurve upon unloading. Unloading occurs when an element made ofsuperelastic shape memory alloy is permitted to revert from asignificantly deformed shape toward its original unstressed shape.Because of the plateau, such an element can maintain an almost constantforce during much of the unloading cycle until just before it iscompletely unloaded.

One form of the present invention provides a surgical instrument whichenables the passage of a ligature around a bone, blood vessel, or othersuch body member, or the grasping of such a body member, withoutrequiring the surgical instrument to be swept over a wide angle ofmotion. The apparatus includes a cannula and, within the cannula, amember which is at least partly constructed of an elastic material,preferably a pseudoelastic material and most preferably a pseudoelasticshape memory alloy, such as those disclosed in U.S. Pat. No. 4,665,906to Jervis, dated May 19, 1987, and U.S. Pat. No. 4,505,767 to Quin,dated Mar. 19, 1985, which are preferred for all forms of this inventionand which are incorporated herein by reference.

Although the following detailed description and the accompanying Figuresillustrate the cannula as having a straight shape, and the elasticmember as being held therein in a straightened configuration, it will beunderstood that the cannula may advantageously be formed with anydesirable shape, such as an arc, and that the elastic member may take onany desirable shape upon extrusion from the cannula.

The straight cannula and curved elastic members are used as examples,only, and should not be interpreted to limit the scope of thisinvention. It will also be understood that although the cannula isdiscussed as being fairly rigid, it may be formed of a plasticallydeformable material, which will allow the surgeon to shape theinstrument to any required configuration. The instrument may also beflexible to be used within the working channel of a flexible endoscope,the lumen of a catheter or to function as a catheter itself.

Furthermore the elastic member may be coated with a suitable material,such as a polymer.

The elastic member has a distal end portion with a specific curved shapewhen not subject to mechanical stress. In a first embodiment, theelastic member is of sufficient strength and rigidity to enable asurgeon to grasp and manipulate a body structure, such as a bone,thereby. In the first embodiment, the elastic member includes a distalend structure which may be a pointed tip or a structure which serves toprotect the patient's body and to prevent complete withdrawal of theelastic member into the cannula. As the elastic member is distallyextended from the cannula, it curves around the body structuresufficiently for grasping and manipulating the body structure.

In a second embodiment, the elastic member may be of less substantialconstruction, and its distal end portion is adapted to retain aligature. In order to pass the ligature around a blood vessel or bone,the surgeon need only place the distal end of the apparatus near thevessel or bone, and extend the elastic member from the cannula, withoutany required lateral angular motion of the cannula. The elastic memberreturns to its specific curved shape as it extends beyond the catheter,wrapping itself around the blood vessel or bone. The ligature may thenbe attached to the distal end of the elastic member, and the elasticmember may be withdrawn into the cannula, to pull the ligature aroundthe vessel or bone. By pre-attaching the ligature to the elastic member,the ligature may be passed around the vessel or bone upon extensionrather than retraction of the elastic member. The apparatus may furtherinclude a means for automatically attaching the ligature to orunattaching the ligature from the elastic member.

The elastic member, if made of pseudoelastic material, will not readilybreak during repeated use, since metal fatigue does not occur underpseudoelastic use conditions. The instrument operates even though thecannula is not swept over any degree of motion. The instrument is of asimple design, and is of relatively low production cost.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1-1 through 1-3 illustrate a first embodiment of the presentinvention.

FIG. 1-1a is a cross-sectional diagram, showing the elastic memberdisposed within the cannula, in a mode in which the elastic member has adistal end structure.

FIG. 1-1b is a cross-sectional diagram, showing a mode in which theelastic member has a pointed distal tip.

FIGS. 1-2A and 1-2b illustrates modes of the elastic member, returningtoward a curved shape and a corkscrew shape upon extrusion from thecannula, respectively.

FIGS. 1-3a, 1-3b and 1-3c illustrate linear, lateral, and axialmanipulation of a bone.

FIGS. 1-4-1-12 illustrate a second embodiment of the present invention.

FIG. 1-4 is a cross-sectional diagram, showing the elastic member fullydisposed within the cannula.

FIGS. 1-5aand 1-5b show alternative modes of the ligature retainer.

FIG. 1-6 shows extension of the elastic member of FIG. 1-5a around ablood vessel.

FIGS. 1-7a, 1-7b, 1-7c, 1-7d, 1-7e, 1-7f illustrate a means forautomatically grasping a ligature which is passed around a blood vessel.

FIGS. 1-8a, 1-8b, 1-8c and 1-8d illustrate an alternative mode ofautomatically grasping the ligature.

FIG. 1-9 illustrates another alternative mode of automatically graspingthe ligature.

FIGS. 1-10a, 1-10b, 1-10c and 1-10d illustrate how the apparatus may beused to pass the ligature and automatically tie a half-hitch knottherein.

FIG. 1-11 shows a sliding sleeve which aids in tying the half-hitchknot.

FIGS. 1-12a, 1-12b, 1-12c illustrate how the apparatus may be used topass the ligature and automatically tie a logger's knot therein.

FIG. 1-13 shows a prior art apparatus, and illustrates the wide angle ofaccess needed therefor.

FIG. 2-1 to 2-6 illustrate the first embodiment of the presentinvention, which longitudinally extrudes an elastic needle through thedistal end of a cannula.

FIG. 2-1a is a cross-sectional view, showing the elastic needle heldinside the cannula in a straightened configuration under mechanicalstreet.

FIG. 2-1b shows partial extrusion of the elastic needle from thecannula, with the extruded portion of the needle returning toward itscurved configuration by elastic shape memory.

FIG. 2-1c shows the needle fully extruded from the cannula, and releasedfrom the cannula insert.

FIGS. 2-2a, 2-2b, 2-2c, 2-2d and 2-2e show alternative modes of thedistal end portion of the cannula insert.

FIG. 2-3 is a view of the distal end portion of the cannula insert,showing a raised release signal tab formed therein.

FIG. 2-4a illustrates an integrally constructed mode of the distal endportion of the first embodiment, showing the enlarged transversedimension of the end portion of the cannula insert.

FIG. 2-4b shows an alternative, non-integral mode of the distal endportion of the cannula insert, formed of a compressible material.

FIG. 2-5 is a view of the distal end portion of the cannula insert,showing an indented distal face therein.

FIG. 2-6 is a cross-sectional view of the proximal end portion of thefirst embodiment, showing a suture retention bobbin within the cannulainsert.

FIGS. 2-7 to 2-10 illustrate a second embodiment of the presentinvention, which extrudes the elastic needle laterally rather thanlongitudinally.

FIG. 2-7a is a cross-sectional view showing a cannula, shaft, andplunger of the second embodiment.

FIG. 2-7b is a cross-sectional view of an alternative mode of theproximal end portion of the second embodiment.

FIG. 2-7c is a cross-sectional view of another alternative mode of theproximal end portion of the second embodiment.

FIG. 2-7d is an enlarged cutaway view of the proximal end portion of thealternative mode shown in FIG. 2-7b.

FIG. 2-7e is a perspective view of the proximal end cap of thealternative mode shown in FIG. 2-7c.

FIG. 2-8 is a cross-sectional view of the distal end portion of thesecond embodiment, showing a suture retention bobbin therein.

FIG. 2-9 is a cross-sectional view of the second embodiment, taken atline 9--9 of FIG. 2-7a, showing grooves in the shaft and cannula, andgroove engaging tabs in the plunger, for causing rotation of the shaft.

FIG. 2-10 is a cutaway perspective view of the distal end portion of thesecond embodiment, showing the unwinding of the curved needle throughthe aperture.

FIG. 2-11a illustrates the present invention being used to deliver theneedle to a deep wound for suturing.

FIG. 2-11b illustrates the present invention being used in arthroscopicsurgery on a knee.

FIG. 2-12 to 2-15 illustrate a third embodiment of the presentinvention, which is used to insert ring clips into tissue to hold awound closed.

FIG. 2-12a is a cutaway view of the third embodiment, illustrating aring clip held therein.

FIG. 2-12b illustrates extrusion of the ring clip.

FIG. 2-12c illustrates an alternative mode of the third embodiment,adapted for use with an extended ring clip which is held therein.

FIG. 2-13a and 2-13b, and 2-13c and 2-13d, illustrate a marker whichindicates a first and a second direction of extrusion of the ring clip,respectively.

FIG. 2-14 is a cross-sectional view of another alternative mode of thethird embodiment, adapted for serial extrusion of a plurality of ringclips held therein.

FIG. 2-15a illustrates yet another mode of the third embodiment, withthe plurality of ring clips held in a magazine.

FIG. 2-15b illustrates an internal piston return spring.

FIG. 2-16a illustrates manipulation of the extended distal segment ofthe ring clip of FIG. 2-12c.

FIG. 2-16b illustrates the severing of the extended distal segment ofFIG. 2-16a.

FIG. 2-17a, 2-17b, 2-17 c illustrates various modes of a ring clip.

FIG. 3-1 is a view of an unexpanded barrier device (not shown) within ahousing.

FIGS. 3-2, 3-3, 3-4 and 3-5 are progressive cross-sectional viewsthrough line a--a of FIG. 3-1, showing the use of the device of FIG.3-1. The figures show, respectively, FIG. 3-2, constrained; FIG. 3-3,expanded (memory); FIG. 3-4, pouched; and FIG. 3-5, withdrawalconfigurations.

FIG. 3-6a, 3-6b, 3-6c and 3-6d shows alternate embodiments of the deviceof FIG. 3-1 through line b--b.

FIGS. 3-7 and 3-8 show alternate embodiments of the barrier member inthe expanded (memory) configuration.

FIG. 3-9a, 3-9b, 3-9c shows cross-sectional embodiments through lineb--b of FIG. 3-7.

FIGS. 3-10a, 3-10b, 3-11a, 3-11b, 3-12a, 3-12b and 3-13 detail alternateexpanded loop configurations.

FIG. 4-1a is a side view of an unexpanded screen device within a duct,placed downstream from the blocking calculus.

FIG. 4-1b shows the screen device, the deployment end of which has beenplaced upstream from the blocking calculus.

FIG. 4-1c shows a screen device which has been expanded upstream from ablocking calculus.

FIG. 4-1d shows a screen device in place after calculus fragmentation.

FIG. 4-2a, 4-2b, 4-2c and 4-2d shows various stages of deployment of atasseled surgical screen.

FIGS. 4-3a, 4-3b, 4-4, 4-4a, 4-4b, 4-4c, 4-4d, 4-5a and 4-5b showalternate embodiments of the surgical screen portion of a device of thisinvention.

FIG. 5-1 is a cross-sectional view of a constrained retractor device.

FIGS. 5-2, 5-3, 5-4, 5-5 and 5-6 show alternate top views of expanded(unconstrained) retractor devices.

FIGS. 5-7, 5-8, 5-9, 5-10 and 5-11 show alternate side views of expandedretractor devices.

FIGS. 5-12 and 5-13 show alternate end views of expanded retractordevices.

FIGS. 5-14 and 5-15 show alternate cross sectional views of constrainedretractor devices, the cross section taken along line a--a of FIG. 5-1.

FIG. 6-1 is an external view of a device of this invention.

FIGS. 6-2 and 6-3 are alternate cross-sectional views of a sheath ofthis invention, the cross sections being taken vertically along thelongitudinal axis of FIG. 6-1.

FIG. 6-4 is an alternate cross-sectional view of a sheath of thisinvention, the cross section being taken vertically along thelongitudinal axis.

FIG. 6-5 is a cross-sectional view of the device of FIG. 1 taken acrossthe longitudinal axis, along line b--b of FIG. 6-1

FIG. 6-6 is a cross-sectional view of the device of FIG. 6-1 takenacross the longitudinal axis, along line c--c of FIG. 6-1.

FIG. 6-7 is a cross-sectional view of a cutting edge of a cutting bladeof this invention.

FIGS. 6-8, 6-9, 6-10, 6-11 and 6-12 are alternate side views of thedevice of FIG. 1 when the cutting blade is deployed.

FIGS. 6-13 , 6-14, 6-15, 6-16, 6-17, 6-18, 6-19 and 6-20 are alternatetop views of typical elastic blades of this invention.

FIG. 7-1 shows an instrument of this invention.

FIG. 7-2a, 7-2b, 7-2c, 7-2d shows the deployment end of a bladedinstrument of this invention.

FIGS. 7-3a, 7-3b, 7-3c, 7-4a, 7-4b and 7-4c are longitudinalcross-sectional views of alternate elastically deployable stems, inlongitudinally constrained and longitudinally unconstrainedconfigurations.

FIGS. 7-6 and 7-5a, 7-5b, 7-6a and 7-6b each show alternate views of anelastically deformable stem of this invention.

FIGS. 7-8a, 7-8b, 7-8c, 7-8d, 7-8e, 7-8f, 7-9a, 7-9b, 7-9c, 7-9d, 7-9e,7-9f, 7-9g, 7-9h, 7-9i show alternate elastic members suitable for usein an elastically deformable stem of this invention.

FIG. 7-10a, 7-10b shows alternate views of a device of this inventionhaving two pivoted blades, each blade having a longitudinal slotproximal the pivot.

FIG. 7-11a and 7-11b, 7-11c shows alternate views of a device of thisinvention having two blades, two bars, and four pivots.

FIG. 7-12a, 7-12b, 7-12c, 7-12d, 7-12e and 7-12d shows alternatecross-sections of the device of FIG. 7-1, taken through line 12--12.

FIG. 7-13a, 7-13b, 7-13c, 7-13e shows various blades suitable for useherein.

FIG. 7-14a, 7-14b, 7-14c, 7-14d and 7-14e shows various bladecross-sections, taken through line 14--14 of FIG. 7-13.

FIG. 1-13 shows the use of a prior art apparatus 700 for passing aligature (not shown) around a particular blood vessel 703 which issituated among other blood vessels 704. In order to place the operativedistal end 710 into a position 715 from which the end 710 is directlyaccessible, it is necessary to swing the entire apparatus 700 through avery wide angle of motion 720. This wide angle requires a very largeentry wound 740 through the patient's tissues 730. It will be understoodthat such a wide angle of motion is impossible to achieve if theapparatus 700 is being used through an arthroscopic or other smallendoscopic surgical entry wound 735 through the patient's tissues 730.

As will be understood from the following description and from theaccompanying drawings, the present invention is an apparatus usablethrough such a small entry wound.

In a first embodiment 100, shown in FIGS. 1-1-1-3, the present inventionincludes a cannula 10 and a member 12. Although the present inventionmay be practiced with a member 12 which is fashioned of anotherappropriate material, such as spring steel, the preferred material is apseudoelastic material, preferably a shape memory alloy and inparticular a shape memory alloy that exhibits superelasticity. Themember 12 will hereinafter be referred to as a elastic member 12, andits distal segment 14 will be referred to as a elastic distal segment14. In a preferred embodiment the member is made of a superelastic shapememory alloy and the elastic distal segment 14 has a first shape whenthe alloy of the elastic distal segment 14 is in a substantiallyaustenitic phase and the distal segment 14 is extended distally from thecannula 10 and is not subject to mechanical stress. The elastic distalsegment 14 may be mechanically stressed into a second shape (i.e. whenthe distal segment 14 is held within the cannula 10), wherein at least aportion of the alloy has changed to a stress-induced-martensite phase.

FIGS. 1-1-a-b show the elastic distal segment 14 elastically deformedinto a second, straight shape within the cannula 10. FIG. 1-2a shows onemode of the first shape, with the elastic distal segment 14 returningtoward an arced first shape upon extrusion from the cannula 10. FIG.1-2b shows an alternative mode of the first shape, wherein the elasticdistal segment 14 returns toward a corkscrew first shape upon extrusionfrom the cannula.

As shown in FIG. 1-1a, the elastic member 12 also includes a proximalsegment 16 which is relatively straight, to allow its easy insertioninto the proximal end of the cannula 10.

The distal and proximal segments may, suitably, be integrally formed ofa unitary wire or rod, or the proximal segment may be formed of adifferent material and coupled end-to-end with a elastic distal segment.If the segments 14 and 16 are formed of a unitary construction, theproximal segment 16 does not, preferably, have a curved shape when it isin an unstressed condition, unlike the elastic distal segment 14.Although the member 12 is referred to herein as a elastic member 12, itwill be understood that, as explained, only the distal end segment 14need be elastic. It will be further understood that the distal endsegment 14 as well as the proximal segment 16 may be formed of anysuitable material, which may or may not be the same.

The elastic member 12 may also include a distal end structure 18, asshown in FIG. 1-1a. The distal end structure 18 is a contact or gripmeans which improves the grip of the apparatus 100 upon an object. Thedistal end structure 18 also prevents the complete withdrawal of theelastic member 12 through the cannula 10, to preserve the apparatus 100as an integral unit. The smooth surface and shape of the distal endstructure 18 serve as a safety means which helps to reduce tissue damageupon insertion of the apparatus 100 into a wound, or through tissue, orthrough an arthroscopic or other such endoscopic surgical entry wound.In the illustrated embodiment, the distal end structure 18 issubstantially semi-spherical, with a diameter roughly equal to that ofthe cannula 10. This protects the patient's tissues from the bluntdistal end of the cannula 10, while also preventing complete withdrawalof the elastic member 12 from the cannula 10. The distal end structure18 may be either unitarily constructed with the elastic distal segment14, or may be formed of a different material and coupled thereto in anyconventional manner. It is to be understood that the distal endstructure 18 can have any blunted shape, and may even be spherical orbullet shaped.

As shown in FIG. 1-1b, the elastic member may have a pointed distal endstructure 19, which, like the distal end structure 18 of FIG. 1-1a,improves the mechanical gripping of the apparatus upon a bone or otherobject. It may be preferred that distal end structure 19 be integralwith the elastic member.

The apparatus 100 may, suitably, be further adapted with a handlestructure for extending the elastic member 12 through the cannula. Inone mode, the handle structure may include a thumb ring 20 coupled tothe proximal end of the elastic member 12, and one or more finger rings22 coupled near the proximal end of the cannula 10. The surgeon insertsthe elastic member 12 through the cannula 10 by pressing on the thumbring 20 while holding the finger rings 22 stationary, and withdraws theelastic member 12 into the cannula by pulling the thumb ring 20 in theopposite direction. Of course, other handle devices are within the scopeof all of the embodiments of this invention, such as a pistol grip, or ascissor-action apparatus, or the like. Withdrawal of the elastic member12 may be assisted by a spring (not shown).

As shown in FIG. 1-2a, when the elastic member 12 is inserted throughthe cannula 10 with motion 24, the elastic distal segment 14 emergesfrom the distal end of the cannula 10. In a preferred embodiment inwhich superelastic shape memory alloy is utilized, the elastic distalsegment 14 has its stress-induced-martensite condition at leastpartially relieved of stress by the absence of any restraining cannula.The alloy of the elastic distal segment 14 undergoes at least a partialreversion toward the austenitic phase, and the elastic distal segment 14returns toward its first shape with motion 26.

It will be understood that the curvature of the elastic distal segment14 need not necessarily be circular, nor coplanar with the axis of thecannula 10, within the scope of this invention. For example, the distalsegment 14 might be formed to curve radially about the axis of thecannula upon extrusion therefrom, in a corkscrew fashion, as shown inFIG. 1-2b. As will be understood, the elastic distal segment 14 may beformed to have any desired shape or arc or radius of curvature, to suitthe apparatus for a given purpose.

As shown in FIGS. 1-3a-c, the apparatus 100 may be used to manipulate abone 3 or other structure in a patient, or any other suitable object.The specific body members which are discussed herein are listed solelyto aid in the understanding of the invention, and do not affect thescope of the invention.

It will be understood that the first embodiment 100 may be constructedin a variety of sizes and with an elastic member of a variety of lateraldimensions, cross-sectional configurations, and strengths, for suitableuse in manipulating a wide variety of body members or other objects. Forexample, a very small apparatus with a very thin elastic member may bedesirable in manipulating small or delicate body members such asindividual nerves or terminal arteries. On the other hand, a largeapparatus with a thick elastic member having great strength may berequired in order to manipulate a larger body member such as a brokenfemur, or a bulky organ, or a prosthesis or other mechanical object.Also the apparatus may be long and/or flexible, so that it can be usedin the channel of an endoscope (rigid or flexible), in the lumen of acatheter, or as a catheter itself.

The elastic distal segment 14 of the elastic member 12 may be insertedinto or wrapped around the body structure 3, and the apparatus 100 maybe moved, to manipulate the structure 3. Extension of the elastic member12 into grasping connection with the body member 3 does not require anylateral movement of the apparatus 100, but only requires linearinsertion of the elastic member 12 through the cannula 10. This permitsthe apparatus 100 to be used in closely confined surgical sites, orthrough a very small surgical opening such as may typically be used togain arthroscopic access to a knee joint, for example.

By forming the elastic distal segment 14 to have a non-stressed shapewhich curves in a particular direction, the apparatus 100 may beconstructed for suitable hooking of a body member which has a givenorientation. With the curvature shown in FIG. 1-3a, the apparatus 100may be suited for linear pulling or pushing of the body structure 3 inthe direction 28 shown. With the curvature shown in FIG. 1-3b, theapparatus 100 may be suited for lateral manipulation of the bodystructure 3 in the direction 30, as shown. As shown in FIG. 1-3c, if theelastic distal segment 14 curves in a corkscrew shape, the apparatus 100may be readily used to push or pull the body structure 3 along the axisof the body structure 3, in direction 32 as shown.

The apparatus 100 may be adapted with a marker 31, as shown in FIG.1-3a, for indicating the direction and orientation in which theparticular elastic member 12 will curve upon extrusion. The marker 31may be, for example, printed upon the cannula 10, or may be a raised orindented portion thereof. As it is desirable that the marker 31 notcause any trauma to an entry wound, a printed marker may be thepreferred mode. It will be understood that the marker may be placed atany desired point along the length of the cannula. For example, a markerplaced immediately adjacent to the distal tip of the apparatus willlikely be visible to an arthroscopic surgeon through his or herarthroscopic viewing apparatus. On the other hand, or in addition, amarker placed near the proximal end of the apparatus will remain inplain sight during surgery, as it will remain outside the patient'sbody. The apparatus 100 may include any suitable means for ensuring thatthe elastic member 12 curve in the indicated direction. For example, thedistal segment 16 may be formed of a square cross-section, with theproximal end opening (not shown) of the cannula 10 being formed of asimilar shape, such that the elastic member 12 cannot rotate within thecannula 10. Alternatively, the cannula 10 may have a peg (not shown)which engages a longitudinal slot (not shown) in the elastic member 12,or the elastic member 12 may have a peg (not shown) to engage alongitudinal slot (not shown) in cannula 10.

FIGS. 1-4-1-12 illustrate a second embodiment 200 of the presentinvention. In this embodiment, the elastic member 12 need not include adistal end structure, and may be fully withdrawn into the cannula 10.Although the second embodiment 200 is hereinafter described as beingused for passing a ligature around a blood vessel, it will be understoodthat the ligature may be passed around any other body structure or otherobject, within the scope of this invention. If the non-deformed shape ofthe distal segment of the elastic member is substantially circular, thishas the important advantage that, during extension and withdrawal of theelastic distal segment, that portion of the elastic distal segment whichis already extruded from the cannula and adjacent the blood vessel willnot apply any lateral or radial forces upon the blood vessel. It will,therefore, be understood that it is advantageous to form differing modesof the second embodiment, wherein each has an elastic member whosedistal segment is of a given radius of curvature in its non-deformedfirst shape. This allows the surgeon to select an appropriately sizedapparatus for passing a ligature around any size of blood vessel, and iswithin the scope of this invention. It will be understood that the sameprinciple applies equally to the first embodiment described above withregard to FIGS. 1-1-1-3. Also the apparatus may be long and/or flexible,so that it can be used in the channel of an endoscope (rigid orflexible), in the lumen of a catheter, or as a catheter itself.

The elastic distal segment 14 of FIG. 1-6 is adapted with a ligatureretainer means 34 which releasably retains the ligature 36. FIGS. 1-5a-bshow the ligature retainer 34 as a hook and a hole, respectively. Ineither mode, the ligature retainer 34 may either be cut into the wire ofthe elastic distal segment 14, or may be bent thereinto by plasticallydeforming the wire of the elastic distal segment 14. Other suitablemeans may be employed without departing from the scope of thisinvention. It will be understood that the ligature retainer 34 may befashioned in any desired orientation relative to the plane of curvatureof the elastic distal segment 14. If the hook mode of the ligatureretainer 34 is used, in order to prevent the hook 34 from catching onthe inner lip 33 of the distal opening of the cannula 10 uponwithdrawal, the lip 33 may be rounded off, as shown in FIG. 1-5a.

The second embodiment 200, like the first, may be adapted with at leastone marker 31 for indicating a predetermined direction of curvature ofthe elastic member, and with suitable handles 20 and 22 or other meansfor extending and retracting the elastic member. A spring may be used toassist retraction of the elastic member 12.

As shown in FIG. 1-6, upon extrusion from the cannula 10, the elasticdistal segment 14 curves around the vessel 5 with motion 38. It will beunderstood that the elastic distal segment 14 need not actually touchthe vessel 5, but is shown in such contact for convenience. With theelastic member 12 wrapped around the blood vessel 5, the ligature (notshown) may be inserted into the ligature retainer 34 using tweezers,forceps, or the like. Withdrawal of the elastic distal segment 14 intothe cannula 10 draws the ligature around the blood vessel 5 with motion40. As will be understood, the ligature may also be inserted into theligature retainer 34 before the elastic distal segment 14 is passedaround the blood vessel 2, in which instance the ligature is passedaround the blood vessel 5 upon extension of the elastic member 12 aroundthe blood vessel 5 with motion 38, if the ligature retainer 34 isappropriately formed.

The apparatus 200 may further be adapted with means for automating theligature's attachment to, or unattachment from the elastic member. FIGS.1-7a-f illustrate one mode of this means. One end 35 of the ligature 36is coupled to the cannula 10, for example by being tied or otherwisecoupled to a post 44. Upon extension from the cannula 10, the elasticdistal segment 14 curves with motion 38 around the vessel 5, as shown inFIG. 1-7b. The elastic distal segment 14 is constructed such that itsreturn toward the unconstrained first shape brings the ligature retainer34 into grasping contact with the held portion 35 of the ligature 36, asshown in FIG. 1-7c.

Upon retraction, the elastic member 12 draws the ligature 36 around thevessel 5 with motion 40 (the reverse of motion 38), and the ligature 36slides through the ligature retainer 34, as shown in FIG. 1-7d. Uponfull retraction, shown in FIG. 1-7e, the ligature 36 will be doubledaround the vessel 5. If it is desired that only a single loop ofligature 36 pass around the vessel 5, this may be accomplished by simplyreleasing the trailing end 37 of the ligature 36, and withdrawing theapparatus 200 until the trailing end 37 passes around the vessel 5, asshown in FIG. 1-7f. Alternatively, a doubled suture (not shown) can beplaced over the post and held by the post such that only one strand ofthe suture is hooked by ligature retainer 34.

The post 44 in the embodiments shown in FIGS. 1-7, 1-9, 1-10, 1-11, and1-12, and the loop grabber 42 shown in FIGS. 1-8 and 1-9, are shown tobe rigidly attached to the cannula 10. However, beth post 44 and loopgrabber 42 could consist of a tongue (not shown) or a cam (not shown) towhich sutures may be attached. Such a tongue or cam would preferably bebiased flush with the wall of the cannula 10 initially, but would bemechanically forced to extend in a direction sideways from the cannulawhen the elastic member 12 is extended from the end of the cannula. Inthis fashion, a suture would be held against the wall of cannula 10until the elastic member is extended, at which time the post and/or loopgrabber would extend sideways from the wall of the cannula 10 such thatthe post 44 will hold the suture in a better location for the ligatureretainer 34, and/or such that the suture can be attached to the loopgrabber 42. Upon withdrawal of elastic member 12 the tongue or cam willpreferably return to their flush position. It is to be understood thatthe configuration of a post or a loop grabber can be a tongue, cam orother suitable structure.

In an alternative mode, the second embodiment 200 may be fashioned suchthat the ligature is passed around the vessel or bone upon extension,rather than retraction, of the elastic member. FIGS. 1-8a-d illustrateone such mode of the apparatus 200. A loop 39 is formed in the ligature36, and the loop 39 is held in the ligature retainer 34, preferablyfacing in the direction in which the elastic distal segment 14 willcurve upon extension from the cannula 10.

The cannula 10 includes a proximal facing loop grabber 42, which may bea hook. Upon extension, the elastic distal segment 14 curves around thevessel 5 and places the loop 39 of ligature 36 over the loop grabber 42.Upon retraction of the elastic member 12, the loop grabber 42 preventsthe ligature retainer 34 from drawing the loop 39 back around the vessel5. If the ligature retainer 34 is a groove or hook, the loop 39 issimply withdrawn therefrom upon retraction of the elastic member 12. Ifthe ligature retainer 34 is a hole or eye, the ligature 36 slipstherethrough upon retraction of the elastic member 12. Forceps can beused, instead of relying On the loop grabber 42, to grasp the ligature36, if desired. In an alternative embodiment, the ligature 36 may beplaced into the ligature retainer 34 as a simple raised strand, to bepassed around the vessel and grasped with forceps.

FIG. 1-9 illustrates an equivalent mode of the apparatus 200 whichpasses the ligature 36 during extension of the elastic member 12. Theloop grabber 42 may be elevated such that it has a segment 43 whichextends beth proximalward and cannulaward. The ligature retainer 34 maybe formed as an eye, through which the ligature 36 is positioned. Thecannula 10 may, suitably, be adapted with a post 44 to which theligature 36 may be anchored. It will be understood that, by forming theelastic distal segment 14 to have a curvature upon extension such thatthe eye 34 is brought into contact with the segment 43 of the loopgrabber 42, and by extending the elastic member 12 until the eye 34extends slightly past the segment 43, the ligature 36 will be forcedover the segment 43 as shown. This and other alternative modes of theligature catching means are within the scope of this invention.Alternatively, a doubled suture (not shown) can be placed over the postand held by the post such that only one strand of the suture is hookedby ligature retainer 34.

In any of the modes, the ligature retainer may include two grooves oreyes on opposite ends of a Y-shaped distal end of the elastic member. Insuch a mode, a segment of the ligature may be held between the arms ofthe Y for presentation to the cannula's hook. This may be advantageousif the loop of the ligature is too limp to be easily caught by thecannula's hook. If formed as a hole, the ligature retainer may include anarrowed, slot-like portion at its proximal end, into which the ligaturemay be wedged. The narrowed portion will provide a tight grip on theloop of ligature during extension about the vessel, while the largerportion of the hole will enable the ligature to easily slip therethroughduring retraction of the elastic member. These, and various othermodifications may be made to the ligature retainer, within the scope ofthis invention.

As shown in FIGS. 1-10a-d, the second embodiment 200 may be used tocreate a knot in the ligature 36. A loop 39 of the ligature 36 is placedaround the cannula 10 in the following manner, as explained withreference to FIG. 1-10a. An end 35 of the ligature 36 is held at somepoint toward the proximal end (not shown) of the cannula 10. Theligature 36 is passed by a first side (the far side in FIG. 1-10a) of apost 44, then over the cannula 10 toward a second side (the near side inFIG. 1-10a) of the cannula 10 at a point distalward from the post 44.From there, the ligature 36 is passed around the cannula 10 back to thefirst side, the around the post 44 proximal to loop 39 on the secondside. The trailing end 37 of the ligature 36 is then drawn toward theproximal end (not shown) of the apparatus 200 to draw the ligature 36 atleast somewhat tight around the cannula 10 and post 44. The post 44 mayinclude a protrusion 46 to keep the trailing end portion 37 of theligature 36 elevated above the cannula 10, for ease of grasping theligature 36. The cannula 10 may include an indented or grooved segment48, to keep the loop 39 of ligature 36 in a given position about thecannula 10.

As seen in FIG. 1-10b, with the apparatus 200 in position at the vessel5, the elastic member 12 may be extended until the ligature retainer 34engages the trailing end portion 37 of the ligature 36. Then, thetrailing end portion 37 alone may be drawn around the vessel 5 as shownin FIG. 1-10c. Finally, by sliding the loop 39 distally off of thecannula 10, with motion 50, until the loop 39 passes completely over andaround the ligature retainer 34, the trailing end 37 may be drawnthrough the loop 39, to form a haft-hitch knot as shown in FIG. 1-10d.The knot may then be tightened, as needed.

FIG. 1-11 illustrates the addition of a sliding sleeve 52, which slidesin and out of the cannula 10. The sleeve 52 is disposed within thecannula 10, and the elastic member 12 is, in turn, disposed within thesleeve 52. Extension and retraction of the elastic member 12 may permitthe sleeve 52 to slide a short, restricted distance. The loop 39 of theligature 36 may be placed over the sliding sleeve 52 rather than overthe cannula 10 itself. Then, after the trailing end 37 has been pulledaround the vessel as described above, the sleeve 52 may be slid into thecannula 10, to dislodge the loop 39. In the final stages of retractingthe elastic member 12 back into the sliding sleeve 52, the elasticmember 12 may engage the sliding sleeve 52 such that the sliding sleeve52 is automatically withdrawn into the cannula 10 and automaticallyreleases the loop 39, if the tolerance between cannula 10 and slidingsleeve 52 is small and the loop 39 cannot readily pass between slidingsleeve 52 and cannula 10. If the ligature retainer 34 is kept within thesleeve 52 during the sliding, the loop 39 will not catch on the ligatureretainer 34. The sliding sleeve 52 may be biased toward its extendedposition by a spring (not shown).

Alternatively, in FIGS. 1-10 and 1-11, end 35 of ligature 36 may befastened to post 44.

FIGS. 1-12a-c illustrate how the apparatus 200, with or without thesliding sleeve, may be used to form a loggers knot around a vessel 5.The ligature 36 is loaded onto the apparatus 200 by simply passing aloop 39 of the ligature 36 over the distal end of the cannula 10, and byplacing beth ends 37 and 35 of the ligature 36 over the protrusion 46 onthe post 44. The elastic member is extended and retracted, to catch andretrieve beth ends 35 and 37 of the ligature 36, as described above.Then, both ends 37 and 35 of the ligature 36 are passed around thevessel 5 and are drawn through the loop 39. Other knots may be tiedusing the apparatus 200, within the scope of this invention. In all ofthe embodiments described herein, any suitable form of activating meansmay be utilized, for example, syringe-plunger mechanisms, slidermechanisms, scissor action mechanisms, pistol grip mechanisms or thelike.

Various other modifications may be made to the apparatus, includingthose suggested by the following description of a "Suturing Instrument".

Another form of the present invention discloses an apparatus and methodwhich, through the properties of elastic materials, preferablypseudoelastic materials, such as pseudoelastic shape memory alloys,overcome the prior art's disadvantages listed above. The apparatus is adelivery system for delivering, into a deep wound or into anarthroscopic, endoscopic, laparoscopic, or other such surgery site, aneedle which is constructed of an elastic material, preferably a shapememory alloy. Although pseudoelasticity is exhibited in both linear andnon-linear variations, the present invention deals preferably withsuperelasticity, and further references to materials having thisproperty will simply be designated as being "pseudoelastic" or havingshape memory. It will be understood, however, that the present inventionmay employ any appropriate elastic material, preferably shape memoryalloy, whether linearly or non-linearly pseudoelastic. The term "needle"as used herein includes solid and hollow needles.

In a first embodiment, the present invention discloses a deep needledelivery apparatus, including a longitudinally extending cannula whichmay be inserted through an arthroscopic or other such incision or into adeep wound or into a natural body orifice. Inside the cannula, theapparatus has a cannula insert member, whose distal end includes a meansfor grasping a needle. The needle is held entirely within the cannula,in a straightened configuration.

Holding the needle within the cannula in a straightened configurationoffers two advantages in reducing trauma to the patient's tissues:because no portion of the needle extends from the cannula duringinsertion of the cannula into the patient's body, the apparatus will notsnag the tissues upon insertion, and because the apparatus has aminimized transverse dimension, only a small entry incision or site isrequired. The minimized transverse dimension may also permit the cannulato be used in a channel of an endoscope (rigid or flexible), in thelumen of a catheter, or as a catheter itself.

The apparatus includes a minimum of moving parts and is, therefore, bothless subject to failure and less expensive than prior needle deliveryapparatuses. The apparatus simplicity of design results in a uniquesimplicity of use, as well.

In a second embodiment, the needle is extruded laterally rather thanlongitudinally, which may permit insertion of the needle into otherwiseinaccessible portions of a patient's tissues.

In a third embodiment, the apparatus inserts ring clips (solid orhollow) rather than a needle.

FIGS. 2-1a to 2-1c illustrate the first embodiment of the presentinvention, a deep needle suturing apparatus 100. The apparatus 100 has acannula 11 and a needle delivery member which is a cannula insert 12.Although the drawings and this description specifically show a cannula11 and cannula insert 12 which are straight and which may be assumed tobe rigid, the cannula 11 and cannula insert 12 may be curved, or mayeven be deformable to some degree, within the scope of this invention.For example, they may be flexible and/or long enough for apparatus 100to be used within a channel of an endoscope (flexible or rigid), in thelumen of a catheter, or as a catheter itself.

The cannula insert 12 has an outer dimension which allows it to fitcoaxially within the cannula 11 and move longitudinally therewithin. Thecannula 11 has a proximal end portion 11p to which are affixed cannulahandles 13 which, suitably, may be finger rings into which a surgeon mayinsert his index and middle fingers. The cannula 11 has a bore 111extending longitudinally therethrough. The bore 111 extends out thedistal end portion 11d of the cannula 11, to allow a distal end portion12d of the cannula insert 12 to extend distally out of the cannula 11. Acannula insert handle 14 is affixed to the proximal end portion 12p ofthe cannula insert 12. The handle 14 may, suitably, be a thumb ringthrough which the surgeon may insert his thumb. By pressing on the thumbring 14 and pulling on the finger rings 13, the surgeon may extend thecannula insert 12 through the cannula 11 with motion 201. It will beunderstood that, within the scope of this invention, various other meansmay be employed to extend the cannula insert through the cannula. Forexample, the apparatus may include a pistol grip with a trigger forextending the cannula insert, or a scissor action mechanism, or thelike.

The distal end portion 12d of the cannula insert 12 grasps an elasticneedle 10. In the preferred embodiment, the needle 10 is of apseudoelastic shape memory alloy and has an arced shape while theneedle's alloy is in a substantially austenitic phase, and the needle 10may be stressed into a more straight shape in which the needle's alloyenters an at least partially more martensitic phase. When the needle 10is held entirely within the cannula 11, as shown in FIG. 2-1a, theneedle 10 is straightened and contains more stress-induced-martensitephase. As the needle 10 is extruded from the distal end portion 11d ofthe cannula 11, that portion of the needle 10 which extends beyond thecannula 11 returns toward its original shape by amartensitic-to-austenitic shape memory phase change caused by at leastpartial relief of the stress-induced-martensite in the needle's alloy.

The cannula insert 12 includes a longitudinal bore 112, which may beused to contain a suture 9 attached to the needle 10. Suitably, the bore112 may extend longitudinally entirely through the cannula insert 12, topermit an unlimited length of suture 9 to be pulled therethrough.Although in FIGS. 2-1a-c the suture 9 is shown exiting through theproximal end of the cannula insert and laterally out of the thumb ring14, the suture 9 may, within the scope of this invention, exit theapparatus in a variety of manners. For example, the suture may exitthrough a small aperture (not shown) in the side wall of the distal endportion of the cannula insert, in which case bore 112 would not have toextend further proximally and the proximal portion of cannula insert 12would be dimensioned such that there would be room for the suture withinbore 111 (i.e., the proximal portion of cannula insert 12 could have asmaller transverse dimension than its distal portion, or it may includea longitudinal slot for the suture). Alternatively, the thumb ring maybe hollow, and the suture may pass directly from the interior of thecannula insert into the interior of the thumb ring, and may exit throughan aperture (not shown) at some point about the thumb ring.

The suture may be attached to the needle in a variety of ways. Forexample, the proximal end of the needle may include a hollow orificewhich may be crimped down upon an end of the suture. Alternatively, aferrule may be used to couple the suture to the needle. Or, a smallwedge-shaped groove may be used to pinch the suture into a slot in theproximal end of the needle. If a more complex needle assembly iseconomically manufacturable, it may be advantageous to form, into theproximal end of the needle, a longitudinal slot or hole which may alsocommunicate with a transverse slot into which a knotted or thickenedportion of the suture may be positioned. Or, it may simply suffice toglue the suture onto the needle.

The distal end portion 12d of the cannula insert 12 includes a means forholding 15, which grips the needle 10, and which is connected to thebore 112. As the distal end portion 12d is distally extended from thecannula 11 with motion 201, the means for holding 15 releases the needle10, permitting the surgeon to manipulate the needle 10 within thepatient, to form stitches or perform other procedures. However, if theneedle 10 is only partially extended from the cannula 11, the means forholding 15 will not yet have released the needle 10, and the cannulainsert 12 and needle 10 may be retracted into the cannula with motion202, to allow repositioning of the needle 10 in the patient.

FIGS. 2-2a through 2-2e illustrate various designs of the means forholding 15 formed in the distal end portion 12d of the cannula insert12. The distal end portion 12d is divided by a slot 16 into a pluralityof end sections 19. Each end section 19 includes a longitudinal groove17, which runs substantially parallel to the axis of the cannula insert12. In one mode, shown in FIG. 2-2a, one slot 16 divides the cannulainsert 12 into two end sections 19, each of which has a flat surfaceinto which the respective grooves 17 are formed. The enlargement in theslot 16, which is formed by the adjoining groves 17, constitutes themeans for holding 15. In other modes, however, a plurality of slots maydivide the distal end portion 12d into three or more end sections 19, asshown in FIGS. 2-2b and 2-2c. If there are three or more end sections19, the grooves 17 lie at a centermost point of the wedge shaped endsections 19. It will be understood that the exact cross-sectional shapeof the grooves 17 is not critical, so long as the grooves 17 remain welladapted to grasp the needle 10. It will be understood that the slot 16may merely be a slit cut into the cannula insert 12, if the material ofthe cannula insert 12 reacts to the slit by flaring outward to allowlater compression of the distal end portion 12d.

With reference to FIGS. 2-1c and 2-4a, it will be understood how themeans for holding 15 grips the needle 10. A proximal, non-piercing endportion 10p of the needle 10 has a transverse dimension 10w, while themeans for holding 15 has a transverse dimension 15w sufficiently largerthan dimension 10w to accept the needle 10 without gripping it. Thedistal end portion 12d of the cannula insert 12 has a transversedimension 12dw perpendicular to the slot 16, and the remainder of thecannula insert 12 has a dimension 12w which is smaller than dimension12dw. The cannula 11 has an internal transverse dimension 11w, which issufficiently larger than dimension 12w to allow the cannula insert 12 tomove freely therewithin. However, because dimension 11w is smaller thandimension 12dw, in order for the distal end portion 12d of the cannulainsert 12 to fit within the cannula 11, the distal end portion 12d mustcompress. It will be understood that by appropriately sizing variousportions of the bore 111, the distal end portion 12d may be caused tocompress at a determinable point along the cannula 11. The compressionneed not occur at the exact distal end of the cannula.

FIGS. 2-2a-e and 2-4a illustrate embodiments of the compressible distalend portion 12d, in which the distal end portion 12d is formed as anintegral, unitary member with the cannula insert 12. As the distal endportion 12d is drawn into the cannula 11, the end segments 19 arepressed toward each other, reducing the widths of the slots 16, whichcauses the grooves 17 to clamp down on the needle 10. However, as shownin FIG. 2-4b, the distal end portion 12d may simply be a separate membermade of a compressible material, such as an elastomer, with or withoutany slots or end sections, which member is coupled to the cannula insert12. In such a mode, the entire distal end portion 12d elasticallycompresses onto a needle held in its means for holding 15. In eithermode, as the distal end portion 12d of the cannula insert 12 is extendeddistally out of the open end of the cannula 11, the distal end portion12d elastically returns toward its original shape, allowing the needle10 to freely slip from the means for holding 15.

FIGS. 2-2d and e may be better understood with reference to FIG. 2-1a.It will be understood that when the needle 10 is held in the means forholding 15, and the needle 10 is disposed entirely within the cannula11, the elastic properties of the needle 10 exert lateral forces uponboth the cannula 11, and the means for holding 15. The straightenedneedle 10 exerts lateral force on the distal end of the cannula insert12 in the direction shown in FIG. 2-2d by arrow 203. The needle 10 has apoint which bears on the cannula 11 at a location opposite the direction203. By forming the means for holding 15 in a position radially removedfrom the center from the cannula insert 12, in direction 203, the needle10 may be held in a less stressed and less straightened configuration,without changing the transverse dimension of the cannula 11.

The slot 16 may be radially removed from the center of the cannulainsert 12, as shown in FIG. 2-2e, to divide the distal end portion 12dinto two asymmetrical end portions 19. A needle 10 held in anorientation so as to curve opposite the direction of arrow 203(generally upward in FIG. 2-2e) will exert a force which isperpendicular to the slot 16 rather than along the slot 16. This helpsprevent the needle 10 from forcing its way out of the means for holding15 and into another position within the slot 16, and ensures a more firmgrasp on the needle 10.

FIG. 2-3 illustrates a needle release indicator formed in the distal endportion 12d of the cannula insert 12. Near the distal end of the cannulainsert 12, a raised release signal tab 20 is formed in the distal endportion 12d. A segment 21 immediately proximal to the tab 20 is radiallyindented relative to the tab 20. Although segment 21 is shown in FIG.2-3 as having a lateral dimension which is smaller than the remainingportions of the cannula insert 12, this is, in various modes of thecannula insert 12, not mandatory. For example, the remaining portions ofthe cannula insert 12 may be of smaller, equal, or greater lateraldimension than segment 21, so long as the cannula insert 12 remainslongitudinally movable within the cannula 11, and so long as the meansfor holding 15 remains able to hold and release the needle 10.

When the distal end portion 12d of the cannula insert 12 is extendedbeyond the distal end of the cannula 11, at the moment the tab 20completely exits the cannula 11, the distal end portion 12d snapsoutward until the segment 21 contacts the cannula 11. This produces atangible or audible signal to the surgeon, indicating that the cannulainsert 12 is emerging from the distal end of the cannula 11, and,depending on the placement of the tab 20 relative to the means forholding 15, may indicate to the surgeon that the needle 10 has just beenor is about to be, released. It will be understood that, byappropriately sizing various segments of the cannula 11 and byappropriately placing the tab 20, the release signal may be made tooccur at any given stage of needle extension. In an alternativeembodiment (not shown), tab 20 can be replaced by one or more elastictabs directed proximally which spring out as distal end portion 12demerges from the distal end of cannula 11.

Once the needle 10 has been released from the cannula insert 12, thesurgeon may use the needle 10 to insert running stitches or regularstitches into the patient's tissues. Once the stitching procedure isfinished, the needle 10 must be withdrawn from the patient's body with aminimum of trauma to the patient. The apparatus 100 of the firstembodiment can also be used in the withdrawal of the needle 10. Bymaneuvering the cannula insert 12 until an end of the needle 10 entersthe means for holding 15, and then distally extending the cannula 11onto the cannula insert 12, the surgeon may recompress the distal endportion 12d of the cannula insert 12, which presses the means forholding 15 onto the needle 10. Then, by withdrawing the cannula insert12 into the cannula 11, the needle 10 may be restraightened and drawnentirely inside the cannula 11. The cannula 11 may then be withdrawnfrom the patient's body with an absolute minimum of trauma. This sameprocess may be used if the needle 10 is badly placed when extruded fromthe cannula 11. The surgeon may simply regrasp the needle 10 in thecannula insert 12, retract the needle 10, and re-extrude the needle 10into a better position. The same process may even be used repeatedly inthe suturing process itself.

In order to ease the process of manipulating the cannula insert 12 backonto the needle 10 for withdrawal, the distal end of the cannula insert12 may include a concave face 22, as shown in FIG. 2-5. The means forholding 15 enters through the distal end of the cannula insert 12 at thedeepest point of the indented face 22. Thus, if the surgeon maneuversthe cannula insert 12 near enough to the needle 10, so that an end ofthe needle 10 is within the indented face 22, during further distalwardmotion of the cannula insert 12, the indented face 22 will guide theneedle 10 into the means for holding 15.

In order to provide a more self-contained apparatus 100, the cannulainsert 12 may include a means for containing a length of suture. In onemode, the means for containing may be a suture release bobbin 25 aroundwhich a length of suture 9 is wound, as shown in FIG. 2-6. As thesurgeon uses the needle 10 to make stitches in the patient, the suture 9is pulled from the distal end of the bobbin 25. By forming the bobbin 25with a slightly conical shape, the suture 9 may be pulled from thebobbin 25 with reduced friction. Reducing the friction between theapparatus 100 and the suture 9 is not only desirable to make suturingeasier for the surgeon, but also to prevent accidental movement of aneedle 10 which has been released within the patient. Such unwantedmovement might be caused by friction between the suture 9 and theapparatus 100 if the apparatus 100 is moved or inadvertently bumped bythe surgeon.

FIG. 2-11a shows how the first embodiment 100 of the present inventionmay be used to repair a deep wound 4 in tissues 3 and 5. The surgeonpositions the apparatus 100 near the wound to be repaired, and extrudesthe needle 10 from the apparatus, as described above. The needle'spiercing distal end 10d first pierces the tissue 5 on one side of thewound 4. Then, as the needle 10 is further extruded from the cannula 11,the needle 10 returns toward its unstressed shape. This curves theneedle 10 through the tissue 5 beneath or near the bottom of the wound4. The piercing distal end 10d of the needle 10 eventually penetratesand then protrudes from the tissue 3 at the opposite side of the wound4. The distal end 10d of the needle may then be grasped to pull theneedle through the tissue 5 and 3 to draw the suture across the wound 4.Knots may then be tied in the suture, or the needle 10 may be repeatedlywithdrawn and extruded from the apparatus 100 to form multiple stitches.The means for holding 15 may be used to grasp the distal end 10d of theneedle during this process, in the same manner described above forwithdrawal of the needle 10. After the distal end 10d emerges from thetissue 3, the surgeon may grasp the distal end 10d in the cannulainsert's means for holding, as described. The surgeon may then pull theneedle 10 and suture through the tissues 5 and 3. The surgeon mayrelease the needle 10, then grasp its proximal end 10p in the means forholding and partially or fully resheath the needle 10 inside the cannula11 preparatory to forming another stitch.

FIG. 2-11b illustrates the first embodiment 100 of the present inventionbeing used in arthroscopic surgery to repair a torn meniscus 6 in a knee7, in much the same manner. It will be understood that, because theneedle 10 provides its own curving suture path as it pierces themeniscus 6, the apparatus 100 need not be swept over any degree ofmotion in order to suture the meniscus 6. The apparatus 100 is capableof performing suturing through an entry wound which is of a minimalsize. The entry wound need only be big enough so that the apparatus 100may slip inside the knee. In other words, the entry wound need only beas big as the lateral dimension of the apparatus 100.

As shown in FIG. 2-7a, a second embodiment of the present invention isan apparatus 200 which extrudes a needle 10 laterally rather thandistally. The second embodiment 200 includes a cannula 30 which issubstantially similar to the cannula of the first embodiment. Apparatus200, which is preferably rigid, can be long and/or flexible enough forapparatus 200 to be used in a channel of an endoscope (flexible orrigid), in the lumen of a catheter, or as a catheter itself. However,the second embodiment's cannula 30 does not have an open distal end.Rather, the second embodiment 200 extrudes the needle 10 through anaperture 31 which is located through a side wall of the cannula 30 nearits distal end. In this application, it is intended that the term"adjacent the distal end", when applied to the location of the apertureor of other equivalent means, indicates that the aperture may openeither through the side wall of the cannula or actually through thedistal end of the cannula.

Inside its distal end, the cannula 30 includes a pivot 34, about which ashaft 29 rotates. The distal end portion of the shaft 29 is a spoolportion 29d about which the needle 10 is wrapped. When used with thesecond embodiment 200, the needle 10 is stressed into a mere curved,rather than a more straightened, shape when disposed within theapparatus. Relief of the stress in needle 10 held in the more curvedconfiguration, then, results in the needle 10 returning toward its morestraight shape which may be a curve suitable for suturing.

Much of the remainder of the shaft 29 includes spiral grooves 27. Aplunger 28 is disposed about the shaft 29 and within the cannula 30, andhas tabs 26 which engage the spiral grooves 27 of the shaft 29. When theplunger 28 is moved into the cannula 30, the tabs 26 and grooves 27impart rotating motion 210 to the shaft 29 and needle 10. When theplunger 28 is withdrawn, the shaft 29 rotates in the opposite direction.

FIG. 2-9 is a cross sectional view of the apparatus 200, taken acrossline 9--9 of FIG. 2-7a, and illustrates the special relationship betweenthe cannula 30, the plunger 28 with its tabs 26, and the shaft 29 withits spiral grooves 27. As will be understood, a functionally identicalequivalent may be constructed by affixing the tabs 26 to the shaft 29,and adapting the plunger 28 with the spiral groves 27. As further shownin FIG. 2-9, the groove-engaging tabs 26 of the plunger 28 may alsoextend outward from the plunger 28, and the inner surface of the cannula30 may also be adapted with grooves 72. By forming the grooves 72 in thecannula 30 to run substantially linear to the axis of the cannula 30,the plunger 28 will be prevented from rotating upon insertion into andwithdrawal from the cannula 30.

As shown in FIG. 2-7b, the tabs 26 may be constructed as a part of thecannula 30. The thumb ring 14 is coupled to the plunger 28 by aswiveling means. In one mode, the swiveling means may be the simplesnap-lock mechanism 28c shown in FIG. 2-7d, which is held in place by anend cap 28b. In this mode, the shaft 29 slidably engages the plunger 28by any non-circular cross-section instead of having spiralled grooves.

With reference to FIGS. 2-7c and 2-7e, it will be understood that theexact means for imparting rotation to the shaft 29 may be formed in avariety of ways within the scope of this invention. For example, thetabs and grooves may be eliminated by simply forming the plunger 28 of aspiral-twisted rod of square cross-section, and providing the cannula 30with an appropriate end cap 57 which has an opening suited forpermitting the plunger 28 to pass therethrough only by appropriaterotation. Other non-circular cross-sections are, of course, within thescope of this invention. Again, shaft 29 slidably engages plunger 28 byany non-circular cross-section instead of having spiralled grooves. Itis to be understood that any suitable activating means, such assyringe-plunger mechanisms, slidings mechanisms, pistol grip actionmechanisms, scissor action mechanisms or the like can be used to depressplunger 28 into cannula 30.

With reference again to FIG. 2-7a, the shaft 29 may contain a repository32 which is a means for containing a length of suture 9. The shaft 29includes a needle stop 24, which prevents the needle 10 from rotatingbackward relative to the shaft 29. In one embodiment, the needle stop 24may simply be a lip on one side of the repository 32, which lip forms ameans for abutting a non-piercing end of the needle 10.

FIG. 2-8 illustrates an alternative mode of the repository 32, in whichthe repository may be a bobbin 33 which contains a length of suture. Thebobbin 33 rotates freely about the shaft 29 with motion 205. This, too,reduces friction between the suture and the apparatus 200, to preventunwanted movement of the needle 10 via the suture, once the needle 10has been completely extruded from the cannula 30.

FIG. 2-10 is a cutaway cross-sectional view of the distal end portion ofthe second embodiment 200, and illustrates the unwinding of the needle10 through the aperture 31. The aperture 31 must have a dimensionsufficient to allow the needle 10 to freely pass therethrough in itsentirety without binding. As the spool portion 29d of the shaft 29rotates relative to the cannula 30, the needle 10 unwinds through theaperture 31 and returns to its unstressed shape. It will be understoodthat the alternative modes shown in FIGS. 2-7b-e are not complete, andmust include appropriate components at their distal ends, much likethose shown in FIG. 2-7a.

As will be understood, the second embodiment 200 may be used in asubstantially similar fashion as described for the first embodiment ofthe deep needle suturing apparatus 100 with reference to FIGS. 2-11a and2-11b, above. The second embodiment 200, however, may be used to providesurgical access to various suturing sites not accessible with the firstembodiment.

In some surgical procedures, stitches are not implanted in a wound. In athird embodiment 300 of the present invention, illustrated in FIGS.2-12a-c, the unstressed shape of the needle may be substantiallycircular to form the needle into a ring clip 8. Only after the wound hashealed are the ring clips removed, if at all.

FIG. 2-12a shows the third embodiment 300 of the present invention,adapted for inserting ring clips 8 (which can be hollow or solid) ratherthan needles. The third embodiment 300 includes a cannula or cylinder 35which is substantially similar to the cannula of the first embodiment.Apparatus 300, which is preferably rigid, can be long and/or flexibleenough for apparatus 300 to be used in a channel of an endoscope(flexible or rigid), in the lumen of a catheter, or as a catheteritself. However, the cylinder 35 has an internal dimension which may bemore similar to the outer dimension of the wire of the ring clip 8 thanis the inner dimension of the first embodiment's cannula to the needle.By forming both the wire from which the ring clip is made and theinternal bore of the cylinder to have a non-circular cross-section, thering clip may be prevented from rotating within the bore. The thirdembodiment 300 further includes a piston 36, whose transverse dimensionis substantially equal to the inner dimension of the cylinder 35. Thepiston 36 need not necessarily contain any means for grasping the ringclip 8, as it is only used to extrude the ring clip 8 from the cylinder35. However, adaptations of the third embodiment 300 which provide meansfor holding and retracting the ring clip 8, similar to those providedfor holding and retracting the needle in the first embodiment, arecertainly within the scope of this invention.

The ring clip 8 is disposed within the cylinder 35, with its distal end8d facing toward the open distal end of the cylinder 35. The piston 36is disposed within the cylinder 35, with the distal end of the piston 36abutting the proximal end 8p of the ring clip 8. Insertion of the piston36 through the cylinder 35 with motion 206 expels the ring clip 8 fromthe cylinder 35 as shown in FIG. 2-12b. As the ring clip 8 is expelled,it returns to its unstressed shape with coiling motion 207, as describedabove for the needle of the first embodiment. Suitably, the ring clip 8may have an unstressed shape which is substantially circular, in orderthat it may pass through a patient's soft tissues with a minimum oflateral pressure, to cause a minimum of structural damage to thetissues.

The third embodiment 300 (as well as any of the embodiments of thisinvention) may be adapted with at least one marker means 55. The marker55 may be, suitably, a raised or embossed portion of the cylinder 35, ormay simply be printed thereon. With the ring clip 8 loaded into thecylinder 35 in an appropriate orientation, the marker 55 will indicatethe direction in which the ring clip 8 will curl when extruded. Thisaids the surgeon in properly clipping a wound. It will be understoodthat any of the various embodiments described herein may also beadvantageously adapted with a suitable marker means. FIGS. 2-13a-b, andFIGS. 2-13c-d, illustrate proper alignment of the marker 55 indicatingtwo respective directions of extrusion of a ring clip 8. The respectivepositions of the marker 55 in FIGS. 2-13a or c indicate that the ringclip 8 will exit the cylinder 35 in the direction as shown in FIGS.2-13b or d, respectively. Marker 55 may be positioned at any suitablelocation along the cylinder. More that one marker may be present.

In another mode, shown in FIGS. 2-12c and 2-16a, the ring clip 8includes an extended proximal segment 49, whose unstressed shape isrelatively straight. This proximal segment 49 may be grasped by thesurgeon in any manner and manipulated, in order to adjust the ring clip8 within the soft tissues. In this mode, the piston 36 has an enlargeddiameter and includes a bore 37 extending into the piston 36. Adaptingthe piston 36 with the bore 37 allows the third embodiment 300 tocontain the lengthened and extended ring clip 8. This obviates the needto lengthen the cylinder 35, making the apparatus 300 easier for thesurgeon to handle. As shown in FIG. 2-16b, after the surgeon hasmanipulated the extended ring clip 8, the extended end segment 49 may beremoved by any conventional method, such as cutting it off with wirecutters. It will be understood that the proximal segment 49 need not beof an elastic material, but may be any conventional material affixed tothe elastic segment 8 in order to minimize the cost of the apparatus300.

The cylinder and piston of the third embodiment of the apparatus may beused with a variety of different ring clips, such as are shown in FIGS.2-17a-c. As shown in FIG. 2-17a, the ring clip 8 may be formed suchthat, in its unstressed configuration, its distal end 8d and proximalend 8p come into end-to-end abutting alignment. Alternatively, as shownin FIG. 2-17b, the ends 8d and 8p may come into side-by-side overlappingalignment. Locking of the ring clip may be permitted by having a smallbarb or barbs (not shown) on end 8d which fit(s) into a recess orrecesses (also not shown) on end 8p or vice versa.

A slightly modified ring clip may include a proximal coupling hook 8ph.In such a configuration, in the ring clip's unstressed configuration,the hook 8ph remains somewhat separated from the piercing end 8d, suchthat the ring clip does not form a complete circle. The surgeon maystress the ring clip into a tighter arc, and engage the hook 8ph withthe piercing end 8d, as shown. The elasticity in the ring clip 8 willcause the hook 8ph to remain engaged under mechanical stress. Such amode of the ring clip is taught in U.S. Pat. No. 5,002,563 (Pyka et al).

As shown in FIG. 2-14, the third embodiment 300 may have a lengthenedcylinder 35, within which may be disposed a plurality of ring clips8a-8n. Injection of the piston 36 through the cylinder 35 then causesserial extrusion of the ring clips 8a-8n.

Serial extrusion of ring clips 8a-8n may also be accomplished byadapting the third embodiment 300 as shown in FIGS. 2-15a or b. In thismode, the third embodiment 300 includes a magazine 38 which holds theplurality of ring clips 8a-8n. The magazine 38 includes a magazinespring 39, which presses on the ring clips 8a-8n to keep them in theirstressed and more straightened shape, and which introduces them seriallyinto the cylinder 35, in position for extrusion by the piston 36. Themagazine 38 may be separately attachable, and may also be refillable. Itwill be understood that any suitable means may be used to keep theplurality of ring clips in any favored orientation, if it is desiredthat they exit the cylinder 35 in a predetermined orientation ofcurvature. For example, the ring clips 8a-8n may be formed of arectangular cross section, or they may be releasably glued together, toprevent their rotation, within the magazine 38, away from theirpreferred orientation.

The third embodiment 300 may further be adapted with a piston returnspring 40, which is compressed upon injection of the piston 36, andwhich automatically returns the piston 36 to a position allowingintroduction of the next ring clip into the cylinder 35. As shown inFIG. 2-15b, the piston return spring 40 may be disposed within thecylinder 35. In this mode, the cylinder 35 includes an enlarged chamber41, within which the spring 40 is disposed. The piston 36 may include anenlarged segment 42, which is disposed within the cylinder 35, and whichis kept inside the cylinder 35 by an end cap 43 on the cylinder 35. Thismaintains the apparatus 300 as a more integral unit, and prevents thecomplete withdrawal of the piston 36 from the cylinder 35. This alsoallows for a precompressed piston return spring 40 to be used, whichprovides greater return strength and speed for the piston 36. It is tobe understood that any of the embodiment of this invention may beactivated by any suitable activating means, such as syringe-plungermechanisms, slidings mechanisms, pistol grip action mechanisms, scissoraction mechanisms or the like.

A third form of the present invention provides an endoscopic orlaparoscopic surgical device which provides an internal drape, andfacilitates tissue collection. The surgical device comprises a housinghaving an axial bore with a distal deployment opening; and a barriermember which is constrainable within the axial bore. The barrier membercomprises a loop of elastically recoverable material, preferably a shapememory alloy, and a barrier membrane loosely spanning the loop. Remotemeans are provided to project and retract, and optionally to rotate, thebarrier member relative to the distal end of the housing. A preferredembodiment uses a shape memory alloy material, especially apseudoelastic shape memory alloy material, and more preferably asuperelastic shape memory alloy material.

The barrier member is moveable between a first position wherein thebarrier member is constrained within the housing, and a second positionwherein the barrier member is extended past the distal deploymentopening of the housing, and assumes an expanded shape. In the expandedshape, the barrier member acts as a surgical drape and/or as a surgicalcollector. The barrier member is preferably moveable to a third positionwherein the barrier member is partially or fully retracted, and at leasta portion of it is constrained within the housing.

During surgery, especially "least invasive surgery" (LIS), it isfrequently necessary to remove diseased tissue. This tissue may beinfected, contain inflammatory secretions (e.g., bile), or contain tumorcells. In any of these situations it is desirable to perform surgerywithout contaminating surrounding healthy tissues with any of thediseased tissue. Expandable internal barriers of this invention minimizeor prevent such contamination. The expandable barrier member comprises(a) a flexible membrane which loosely spans (b) a loop of elasticallydeformable material. The elastically deformable loop is preferably apseudoelastic shape memory alloy which defines an expanded loop in its"memory" shape. The expandable barrier is constrained within a housing,and the deployment end of the housing is placed within a body. Thebarrier is deployed from the housing and expands to its memory shape.

The barrier can be placed under diseased tissue, so that undesiredmaterials spill into the barrier by gravity and/or irrigation flow,without contaminating surrounding tissues. The undesired materials canbe aspirated from the surface of the barrier prior to withdrawal of thedevice. Alternatively, the barrier is placed so that it substantiallysurrounds and encloses the diseased tissue and sequesters it fromhealthy tissue during surgery. The tissue sample is severed (ifnecessary). In a preferred embodiment, when the elastically deformableloop is first withdrawn back into the housing, the barrier membraneremains suspended outside the housing. The upper edge of the barriermembrane closes to form a pouch as the elastically deformable loop isretracted into the housing. Within the pouch is a tissue sample or othermaterial which has been enclosed by the membrane. The housing, barrierand enclosed materials are removed from the patient.

The Figures are drawn for purposes of clarity and are not drawn toscale. Like numbers represent like structures.

FIG. 3-1 is a lateral external view of a device according to the subjectinvention. The housing 10 includes a deployment end 12 which is insertedinto the patient and which houses the expandable barrier member (notshown) in a constrained configuration; a shaft portion 14 which may bepartially or completely inserted within the patient body; and anactuator end 16 opposite the deployment end, which is retainedsubstantially outside the patient. The housing 10 can be flexible orrigid, and its rigidity can vary along its length. A remote actuatormeans 18 is used to project and/or retract, and, optionally, to rotatethe barrier member relative to the distal deployment opening 24.

FIGS. 3-2 through 3-5 show the use of a device of this invention toobtain a tissue sample. They are simplified cross sectionalrepresentations of the device shown in FIG. 3-1, the cross section beingtaken along line a--a. In use, the device is partially inserted into ahuman or animal patient (not shown). The housing can be inserteddirectly into a patient, or the device can be emplaced using aninstrument channel of a standard endoscope, laparoscope, catheter, orthe like.

FIG. 3-2 shows a cross-section of the device of FIG. 3-1 with theexpandable barrier member 22 in a first, constrained configuration.

The housing 10 is preferably an elongate sheath, having an axial bore 20therethrough, the axial bore being sized to receive the expandablebarrier member 22 in a constrained configuration. The axial bore 20opens to the environment at the deployment opening 24. In one embodiment(not shown), the axial bore also opens to the environment at theactivator opening 26, and access for additional laparoscopic orendoscopic devices, and/or fluid access or withdrawal, is provided. Aseal (not shown) may be added at the activator opening 26, to minimizeor prevent fluid (i.e., liquid or gas) leakage.

The specific configuration and dimensions of the axial bore 20 will varywith the use of the device, the parameters of the barrier member 22, andwhether access for additional laparoscopic or endoscopic devices isprovided. In general the axial bore 20 will have an internal diameter offrom less than about 0.3 cm to about 2 cm or greater, preferably fromabout 0.25 cm to about 2.5 cm. In one embodiment (not shown), the axialbore comprises a working channel of an endoscope. Such an endoscope canalso provide surgical implements such as lasers, scalpels, irrigationand aspiration means, visualization means, and the like.

The outer diameter of the housing 10 will vary with the application, thesize of the expandable barrier, and whether additional working channelsare included in the device. The housing in a laparoscopic device willhave a diameter of from less than about 1 mm to about 3 cm or greater,preferably from about 0.4 cm to about 1.5 cm. The length of laparoscopicdevices will be from less than about 10 cm to about 30 cm or greater,mere generally from about 20 cm to about 30 cm. The housing 10 of adevice intended for endoscopic use will have a diameter of from lessthan about 1 mm to about 3 cm or greater. The length of endoscopicdevices will be from less than about 10 cm to about 1 meter or greater.

The barrier member 22 is extended through the deployment opening 24remotely. The barrier member 22 can be attached through the actuatoropening 26 of the housing 10 by a connecting means 28. The connectingmeans 28 can be, for example, soldered or otherwise affixed to thebarrier member 22, as shown. Alternatively, it can be a continuation ofthe elastic material used in forming the elastically deformable loop 36.In the shown configuration, the barrier member 22 is attached to theremote actuator means 18 by the connecting means 28. Longitudinal axialmovement of the activator means 18 relative to the housing 10 causes thebarrier member 22 to be extended from, or retracted into, the housing10, via the deployment opening 24. Rotational movement of the activatormeans 18 relative to the housing 10 causes the barrier member 22 to berotated. If rotational movement is not desirable, a means to preventrotation can be employed.

In the depicted configurations, the remote actuator means 18 slidablyengages the activator opening 26. The remote actuator means 18 can be anextension of the elastically deformable loop 36, or of the connectingmeans 28, and be substantially independent of the housing 10.Alternatively, the remote actuator means 18 can be connected to theconnecting means 28.

The housing 10 includes, or provides integration with, a surgicalhandling apparatus to deploy and retract the barrier member. In oneembodiment, as shown, two finger rings 30 are part of the actuator end16. An additional thumb ring 32 is part of the remote actuator means 18.These rings are for ease of handling. Knobs or ridges, for example, canbe provided for ease of integration with a separate actuator means (notshown). Suitable actuator means include slider mechanisms, pistol gripor thumb actuated mechanisms, scissors handles, and syringe-plungermechanisms (similar to the configuration shown in FIGS. 3-2 through3-6). These and others are well known to the art. The specific type ofactuator mechanism is generally determined by the personal preference ofthe surgeon.

In use, the deployment end 12, and possibly the shaft portion 14, isinserted into the patient. The housing can be inserted directly into thepatient, or it can be introduced using the instrument channel of astandard LIS device. The deployment end 12 possesses lateral integritysuch that it is not significantly deformed by the pressure exerted bythe constrained barrier member 22. In a device having a rigid housing(the usual case for a laparoscopic device), the deployment end 12 of thehousing can be integral to the shaft portion 14 of the housing, suchthat there is no obvious demarcation between the functional zones. Whena device of this invention functions as a catheter (typical withendoscopic use) and there is little lateral support, the deployment end12 may require reinforcement to provide consistent constraint of theexpandable barrier member.

The shaft portion 14 of the housing is located between the actuator(non-inserted) end 16 and the deployment (inserted) end 12 of thedevice. The shaft portion 14 of the housing may be inserted into thepatient (not shown) partially or completely. The shaft portion 14 of adevice which is used in laparoscopy must have sufficient structuralintegrity that it is easily inserted through a surgical opening into thebody of the patient without undue deformation. Materials with sufficientstructural rigidity include stainless steel and rigid polymericmaterials such as plastics.

The material of the shaft portion 14, and the material of the deploymentend 12, can be the same, or can have different physical properties. Forexample, the shaft portion 14 of an expandable barrier device housingused in endoscopic surgery will generally be flexible, to allowinsertion through naturally occurring orifices, ducts, and/or passages,or to allow insertion through the working channel of an endoscope.Suitable polymeric material includes polytetrafluorethylene,polyurethane, polyethylene, teflon, and the like. The material of such aflexible housing may be reinforced at the deployment end 12 with fibers,rings, or longitudinal ribs, for example, to enable it to withstand theforces exerted on it by the barrier member 22 while it is constrainedwithin and deformed by the housing.

The barrier member 22 has two components: the barrier membrane 34, andthe elastically deformable loop 36.

When expanded, the barrier member 22 can have a diameter of from about 1cm or less to about 5 cm or greater, more generally from about 2 cm toabout 4 cm. The barrier membrane 34 spans the elastically deformableloop 36 loosely, forming a rounded plate or bowl. The depth of arcdescribed by the barrier membrane 34 when suspended from the elasticallydeformable loop 36 is from less than about 1 cm to about 7 cm orgreater. In general, the preferred depth of the pouch formed by thebarrier membrane 34 will be less when the barrier membrane 34 is usedprimarily as a tissue protecting surgical drape, and will becorrespondingly greater when the barrier membrane is used as a pouch tocollect tissue or to remove tissue in toto from the surgery site. Inthose embodiments in which a relatively deep bowl-like pouch is present,it may be desirable to reinforce the barrier membrane. Reinforcing staysor ribs, made of, for example, plastic, thickened barrier membranematerial, or a shape memory alloy, provide reinforcement, and assist thebarrier membrane to deploy fully into the desired shape.

The barrier member 22 is compressed and loaded within the axial bore 20.In this constrained configuration, the barrier device can be sterilized,packaged and stored for later use. Preferably at least one expandablebarrier device is available during surgery: when needed, the surgeon canvisually assess the size of the barrier member necessary for tissueprotection and/or collection, and select an appropriate expandablebarrier device.

When constrained, the barrier membrane 34 is collapsed, and may befurled around the elastically deformed loop 36. The barrier membrane ispreferably made of a flexible and impermeable biocompatible material.The composition of the barrier membrane will reflect the specific use ofthe expandable barrier. The barrier membrane is sufficiently thin thatit can be folded or gathered, together with the elastically deformableloop, to fit within the axial bore 20.

In one preferred embodiment, the barrier membrane material issubstantially impermeable to body fluids and other liquids, such asnormal saline solution, which might be present during surgicalprocedures. The thickness of the membrane is sufficient to provide aneffective barrier to noxious or contaminated materials such as bile,spillage from inflamed or infected tissues, or tumor cells. Suitablematerials include polyethylene, polyvinyl chloride, urethane, siliconerubber, and the like.

In an alternate preferred embodiment, the barrier membrane material issubstantially impermeable to tissue samples, but is generally permeableto body fluids and other liquids, such as normal saline solution, whichmight be present during surgical procedures. In this embodiment, thebarrier membrane material can be a net, web, or grid. Suitable materialsinclude perforated, webbed or netted polyethylene, polyvinyl chloride,urethane, silicone rubber, and the like. A similar construct can be madeof, or contain, shape memory materials.

The elastically deformable loop 36 is a wire, or a strip of elasticmaterial. The term "elastic material" is used herein to mean a metallicmaterial that has spring-like properties, that is, it is capable ofbeing deformed by an applied stress and then springing back, orrecovering, to or toward its original unstressed shape or configurationwhen the stress is removed. The elastic material is preferably highlyelastic. The material are metallic. The use of metals such as shapememory alloys is preferred. Shape memory alloys that exhibitpseudoelasticity, in particular superelasticity, are especiallypreferred. The elastic materials herein exhibit greater than 1% elasticdeformation, more generally greater than 2% elastic deformation.Preferably, the elastic materials herein exhibit greater than 3% elasticdeformation, more preferably greater than 4% elastic deformation.

FIG. 3-3 shows the device of FIG. 3-2 in an expanded position. Theremote actuator means 18 has been moved distally along the axial bore20. The elastically deform able loop 36 extends past the confines of thedeployment opening 24. Once the elastically deformable loop 36 isreleased from the compression of the housing 10, the loop regains itsunconstrained, memory, shape and the barrier member 22 attains itsdeployed configuration. While the elastically deformable loop 36 isshown as generally circular or oval, other shapes are also possible.Elliptical, rounded, square, and irregular shapes are also possible, andmay be desirable for a particular application.

The barrier membrane 34 is connected to the elastically deformable loop36. As the loop expands, the barrier membrane 34 unfurls to form agenerally plate-like or bowl-like enclosure having a mouth 38. Theperimeter, or the mouth 38, of the barrier membrane 34 is defined by theintersection of the elastically deformable loop 36 and the barriermembrane 34.

The more bowl-like configuration, shown in FIG. 3-3, is generallypreferred when the device is used to collect or retrieve tissue samples.In use, the expanded barrier member 22 is suspended internally at ornear the surgical site. The barrier can be manipulated to underlie thesurgical site, so that fluids or other materials which are released atthe surgical site flow gently downhill into the expandable barrier bymeans of irrigation flow and/or gravity. When the barrier membrane 34 isbowl-like, it can substantially contain a tissue sample 40 to be excisedand removed during surgery.

FIG. 3-4 shows the device of FIG. 3-3 in a pouched configuration,partially between the expanded configuration of FIG. 3-3 and thewithdrawal configuration of FIG. 3-5. The remote actuator means 18 hasbeen moved proximally along the inside of the axial bore 20. Theelastically deformable loop 36 extends only partially past the confinesof the deployment opening 24, and constraining force of the housing 10has forced the elastically deformable loop 36 into a deformed,semi-constrained shape. The barrier membrane 34 can preferably sliderelative to the elastically deformable loop 36. The barrier membrane 34is preferably not retracted into the housing 10 with the elasticallydeformable loop 36, and remains substantially outside of the housing 10.As the elastically deformable loop 36 is withdrawn into the housing 10,the barrier membrane 34 catches on the deployment opening 24 of thedeployment end 12 of the housing 10. Therefore, the diameter of themouth 38 of the barrier membrane 34 becomes reduced as compared to theexpanded configuration shown in FIG. 3-3, and the barrier membrane 34forms a pouch. The tissue sample 40 is substantially enclosed in thepouch.

FIG. 3-5 shows the device of FIG. 3-4 in a configuration for withdrawalfrom the body. The remote actuator means 18 has been moved further alongthe axial bore 20 in the proximal direction, and is in approximately theposition from which it started. The elastically deformable loop 36 issubstantially fully retracted into the axial bore 20, and constraint ofthe housing 10 has deformed the elastically deformable loop 36 to fitwithin the axial bore 20. The mouth 38 of the barrier membrane 34 isretracted into the housing 10 with the elastically deformable loop 36,preventing any undesired loss of tissue or fluids from within the pouch.The body of the barrier membrane 34, containing the tissue sample 40,remains substantially outside of the housing 10. In this configurationthe device is withdrawn. As the filled pouch of the barrier membrane 34is generally larger than the deployment opening 24, there is a tendencyfor the barrier membrane 34 to seal against the deployment opening 24 ofthe housing 10. This tendency can be enhanced by placing a seal orgasket means (not shown) at the deployment opening 24.

While the demonstration of the device as shown in FIG. 3-1 through FIG.3-5 is representative of one embodiment of a device of this invention,other embodiments are also within the scope of the invention. Forexample, in an alternate embodiment, not shown, the barrier membrane 34is adhered to the elastically deformable loop 36, so that as the mouthof the barrier membrane 34 is withdrawn into the housing 10 it is onlycollapsed transversely as the elastically deformable loop 36 iswithdrawn into and contained within the axial bore. In yet anotherembodiment, the barrier membrane and tissue sample are completelywithdrawn into the housing for removal from the body.

The pouched barrier membrane can provide a transfer means for tissueswhich have been removed from a patient and are to be delivered, forexample, to a pathology laboratory. The entire barrier device can bedelivered, or the distal end of the device including the pouched barriermembrane can be separated from the rest of the device and delivered (notshown). If such a transfer is desired, the barrier membrane can be linedwith, can contain, or can be filled with a tissue preservative.

FIG. 3-6 shows representative embodiments of a cross-section through thehousing, taken along line b--b of FIG. 3-1. A barrier membrane wouldnormally be enclosed within the housing in a folded, bunched, or furledconfiguration. For simplicity, however, the barrier membrane is notshown.

FIG. 3-6a shows a housing 110 having a circular cross-section. This is apreferred cross-section for an expandable barrier device of thisinvention. A circular housing cross-section has the advantage of beingdeformable in any radial direction. A circular housing cross-sectionalso permits delivery of an expandable barrier of this invention througha standard laparoscopic trocar, or through the instrument channel of astandard endoscope. However, other cross-sections may be preferable.

Within the axial bore 120 is the elastically deformable loop 136, whichhas been constrained to fit within the axial bore 120. The elasticallydeformable loop 136 is shown having an elongated oval cross-sectionalshape. This is a preferred cross-sectional shape, as it permitsstructural rigidity of the expanded loop in a direction perpendicular tothe general plane of the loop, but does not compromise the lateralcompressibility of the loop within the general plane of the loop.However, the elastically deformable loop 136 can have any appropriatecross-sectional shape.

The axial bore 120 can provide access for auxiliary implements such asan electrocautery device, laser, knife, probe, or other surgicalimplement, an imaging means, or an irrigation or aspiration means.Auxiliary implements can be an integral part of the device asmanufactured, or can be introduced as needed through the axial bore 120.

FIG. 3-6b shows a housing 110 which has an oval cross-sectional shape.Within the axial bore 120 is the elastically deformable loop 136, whichhas been constrained to fit within the axial bore 120. The elasticallydeformable loop 136 is shown with a rounded cross-sectional shape. Alumen 142 is present. The lumen 142 can have any desired cross-sectionalshape. The lumen 142 is used to introduce auxiliary implements to thesurgical site. Auxiliary implements can include, for example, anelectrocautery device, laser, knife, probe, or other surgical implement,an imaging means, or an irrigation or aspiration means. Auxiliaryimplements can be an integral part of the device as manufactured, or canbe introduced as needed through a provided lumen 142.

FIG. 3-6c represents an embodiment in which a cautery wire 144 isprovided as an integral part of the expandable barrier device. Variouscautery wires are known in the art and are suitable for use with thisinvention. In the pictured embodiment, the cautery wire 144 is a loopthrough which electrical current can flow. It is located adjacent to themouth of the barrier membrane when both the expandable barrier and thecautery wire are deployed. Insulation 146 can be provided aroundsections of the cautery wire, for protection of tissues and of thehousing. The cautery wire 144 is used to sever and/or cauterize tissues,which are preferably collected within the expanded barrier member. Thedeployment and retraction of the cautery wire can be controlled usingthe same actuator as that which deploys and retracts the expandablebarrier element. Alternatively, a second actuator mechanism can besupplied for deployment of the cautery wire.

The cautery device can be made of any suitable material. If the cauterydevice is rigid, then the size of the cautery device is either limitedto the size of the lumen 142, or it protrudes from the deployment end ofthe lumen at all times. However, the cautery wire can comprise anelastic material. In a preferred embodiment, the cautery wire is a loopof wire, and the loop is constrained within the lumen 142 while theexpandable barrier device is placed within the body. In an alternateembodiment, the cautery wire is a hook-shaped span of elastic materialwhich can be linearly constrained within the lumen 142.

It has been discovered that an improved cautery device can be made of ashape memory alloy. The use of an SMA which exhibits pseudoelasticityhas the advantage that the amount of elastic deformation that isavailable is large compared with that available from many otherelectrically conductive materials. The large amount of elasticdeformation of the alloy allows the loop to have a small transversedimension when it is constrained within a housing.

FIG. 3-6d shows the cautery wire 144 located within the elasticallydeformable loop 136. This arrangement permits the cautery wire 144 to bewithin the mouth of the barrier membrane. It also permits the cauterywire and the elastically deformable loop to be contained in the samelumen of the housing. The deployment of the cautery wire can becontrolled using the same actuator as that which deploys and retractsthe expandable barrier element. Alternatively, a second actuatormechanism can be supplied for deployment of the cautery wire. Otherembodiments (not shown) include adhering the cautery wire to the mouthportion of the expandable barrier, or having the elastically deformableloop itself function as a cautery wire, with the barrier membrane beingperforated at specific locations to permit electricity or heat flow tothe tissue. Alternatively, a conductive polymer which can beelectrically heated from outside the body can be used to line the mouthportion of the barrier membrane, or the barrier membrane itself cansupport the flow of heat or electricity through its body. Insulation 146can be provided within the housing, for protection of the housing.

FIG. 3-7 and FIG. 3-8 demonstrate alternative embodiments of theexpandable barrier of this invention.

FIG. 3-7 shows a shallow barrier member 222 wherein the depth of thebarrier membrane 234 is a fraction of the diameter of the mouth 238. Theconnecting means 228 fastens to a circular elastically deformable loop236 which forms a closed ring. This type of expandable barrier membercan function as an internal surgical drape. The housing 210 is shown.

FIG. 3-8 shows another embodiment of this invention. The barrier member222 is relatively deep: the depth of the barrier membrane 234 is greaterthan the diameter of the mouth 238. The connecting means 228 are wireswhich are continuations of the elastically deformable loop 236. Theelastically deformable loop 236 is retained within an enclosure 248formed of the barrier membrane 234. The barrier membrane 234 ispreferably folded over itself, and self-adhered to form the enclosure248. The elastically deformable loop 236 enters the enclosure throughopenings 250. Each end of the elastically deformable loop 236 canindependently enter the enclosure at opening 250, as shown.Alternatively, both ends of the elastically deformable loop 236 canenter the enclosure through one opening 250, not shown. The elasticallydeformable loop 236 slidably engages the loop enclosure 248: in anespecially preferred embodiment, the barrier membrane forms a closedpouch upon retraction of the elastically deformable loop within thehousing when the barrier member is used to collect a tissue sample, asshown in FIG. 3-5.

Also shown in FIG. 3-8 is a cautery wire 244 which, when deployed, islocated proximal the mouth 238 of the barrier member 222. An insulatingsheath 252 is located within the axial bore which houses the cauterywire and projects slightly from the distal end of the housing 210.

While a self-adhered barrier membrane 234 is shown, alternateembodiments are possible. FIG. 3-9 presents some of the alternatives incross-sectional view, the cross-section being taken through line b--b ofFIG. 3-7. The barrier membrane 234 can be a doubled sheet with theelastically deformable loop 236 between the two surfaces, as shown inFIG. 3-9a. The doubled sheet can be self-adhered if desired. The barriermembrane 234 can include rings 260 formed either of the membranematerial or of some other material as shown in FIG. 3-9b. The barriermembrane 234 can be punctured by the elastically deformable loop 236, asshown in FIG. 3-9c. Alternately, the barrier membrane 234 can be affixedto the elastically deformable loop 236 so that sliding of the membranematerial over the elastically deformable loop is substantially impeded(not shown).

FIGS. 3-10, 3-11 and 3-12 show some alternate top and side views of theelastically deformable loop in the expanded, "memory" configuration.FIG. 3-10 shows a closed circular loop 336, with a connecting means 328.The housing 310 is shown. The elastically deformable loop is flat inside view. FIG. 3-11 shows a circular loop 336, in which the connectingmeans 328 is a continuation of the loop. The loop is flat in side view,and the elastic connecting bar is sharply angled. FIG. 3-12 shows anoval loop 336 in top view, in which the connecting means 328 is acontinuation of the elastically deformable loop. The loop is curved inside view, and the connecting bar is gently angled.

The devices of this invention, including the housing and the barriermember, can be reusable. Preferably the device is disposable orsemidisposable. The barrier member and the housing are generallydisposable, and the remote actuator means is either reused or discarded.

A possibly advantageous variation of this form of the invention is shownin FIG. 3-13, which shows an arrangement which can be used to insert acatch bag 434 through a trocar entry, deploy the bag, and allow theremoval of the insertion device prior to removal of the bag itself.Other devices have not allowed for dissociation of the bag and insertiondevice.

The principle feature of this variation is the replacement of the closedloop of metal in the cuff 448 of the bag by two curved arms 436, joinedin the shaft 410 of the instrument, with their tips meeting at thedistal portion of the cuff. Also in the cuff 448 is a drawstring 490looping completely around the cuff, with ends passing through the shaft410 of the instrument, and fastened to the actuation handle 448, in amanner which lets the drawstring move with the arms keeping thedrawstring essentially taut.

Initial insertion of the device is accomplished with the bag 434disposed around the straightened arms 436, all situated in theinstrument shaft 410.

Separating the ends 491 of the strings 490 from the insertion toolexternal to the body will allow the insertion tool to be withdrawn. Thearms 436 will slide out of the cuff 448, and the drawstring ends 491will pass through the shaft 410. This will leave the bag 434 behind withthe drawstring ends coming out of the trocar. An internal pressure sealmay be affected at the proximal end of the shaft 410 or within theshaft.

In a fourth form of the present invention, a remotely operated devicecomprises an elongate housing, and an elastic surgical screen which canbe constrained within the housing. The surgical screen is deployablefrom within the housing to assume an expanded memory shape. In theexpanded shape the surgical screen can have any of several functions.The screen can act as a duct screen, to collect calculi or calculusfragments, and to prevent the movement of calculus fragments in anundesired direction. The screen can act as an emboli screen, to preventthe movement of emboli at or near an operative site. The screen can actas a surgical tool, to hold or maintain a mass, such as a tissue mass,in a localized area. Generally, the screen is removed from the patientin its expanded memory shape, simultaneously removing calculi orresidual calculus fragments, emboli or emboli fragments, or otherinternal masses. The surgical screen is preferably moveable to a thirdposition wherein the surgical screen is partially or fully retracted,and at least a portion of it is constrained within the housing.

The surgical screens of this invention are deployed with radialasymmetry from the mouth of the delivering catheter, and are able totraverse substantially the entire width of a duct with a screeningmeans. The elastic screen comprises, for example, one or more loops ofelastic material, which may be partially or completely spanned by asemipermeable material; a graduated series of a loops; or a tassel.Remote means are provided to project, retract and/or rotate the screenmeans relative to the distal end of the housing.

A method of this invention for removing an internal obstructioncomprises (a) inserting a catheter end beyond an obstruction; (b)deploying a surgical screen from the catheter end; and (c) retractingthe surgical screen to remove the obstruction.

A further method of this invention comprises (a) inserting a catheterend beyond an obstruction; (b) deploying a surgical screen from thecatheter end; (c) fragmenting the obstruction; and (d) removing thesurgical screen to remove obstruction fragments.

An alternate method of this invention comprises (a) inserting a catheterend beyond an obstruction; (b) deploying a surgical screen from thecatheter end; (c) fragmenting the obstruction; (d) retracting thesurgical screen into the catheter; and (e) removing the catheter.

Yet another method of this invention comprises (a) inserting a catheterend beyond an obstruction; (b) deploying a surgical screen from thecatheter end; (c) fragmenting the obstruction; (d) removing obstructionfragments from the operative site; (e) retracting the surgical screeninto the catheter; and (f) removing the catheter.

The devices of this invention have a variety of potential uses. Asurgical screen of the invention herein can be used to capture anundesired mass from within a duct, for example, for removing a gallstonefrom the bile ducts; for removing a kidney stone from the urinarysystem; or for removing an emboli from a blood vessel. Alternatively,the surgical screens can be used during an operative procedure, such asto contain or hold a discrete mass for further procedures or forremoval. For purposes of example only, and not as a limitation,reference will be made to calculi produced by a kidney and removed froma ureter using an endoscopic device. It is to be understood that this isfor simplicity of example only, and that the apparatus, methods andteachings will be similarly applicable a variety of uses.

As used herein, the term "screen" refers to a structure which isscreened, perforated, tasseled, or sieve-like, or which functions toseparate larger particulate matter from smaller particulate matter, or,more preferably, to separate solid matter from fluids.

As used herein, the term "surgical screen" refers to a screen meanswhich is comprised of an elastic material, preferably a shape memoryalloy, and more preferably a pseudoelastic shape memory alloy. Thesurgical screen is compressible for delivery to the operative site. The"operative site" can be, for example, a surgical site, a biopsy site,the site of an angioplasty procedure, the site of a diagnosticprocedure, and the like. Once present at the operative site the surgicalscreen is deployed from the housing, expands to its memory shape, andsubstantially spans the width of the duct. A tissue "mass" refers to adiscrete unit of tissue, a calculus, an embolus, a prosthetic device,and the like.

The surgical screen preferably demonstrates radial asymmetry: it is notdeployed radially from the housing opening. When deployed from thecatheter, the surgical screen is unconstrained, and expands to traversethe duct. In general, at least 80% of the width of the duct will bewithin the perimeter of the surgical screen. More preferably, thesurgical screen is slightly larger than the diameter of the duct, andgently expands apart against the walls of the duct when in the expandedconfiguration. When the surgical screen is used to localize a tissuemass outside a duct, the mass is preferably contained at the surface ofthe surgical screen. Preferably two or more surgical screen devices ofdifferent sizes are available during a procedure. When needed, thesurgeon assesses the size of screen necessary for tissue protectionand/or internal mass collection, and selects a screen which has anappropriate size, shape and/or filter pore size.

The surgical screen is one or more wire or a strip of elastic material.The term "elastic material" is used herein to mean a material that hasspring-like properties, that is, it is capable of being deformed by anapplied stress and then springing back, or recovering, to or toward itsoriginal unstressed shape or configuration when the stress is removed.The elastic material is preferably highly elastic. The material can bepolymeric or metallic, or a combination of both. The use of metals, suchas shape memory alloys, is preferred. Shape memory alloys that exhibitpseudoelasticity, in particular superelasticity, are especiallypreferred. The elastic materials herein exhibit greater than 1% elasticdeformation, more generally greater than 2% elastic deformation.Preferably, the elastic materials herein exhibit greater than 3% elasticdeformation, more preferably greater than 4% elastic deformation.

The surgical screen differs from the prior art in several key aspects.The surgical screen is not radially deployed from the housing, nor isthe housing preferably centered in a duct when the screen is expanded,as has been the case in the prior art. Prior art stone baskets, forexample, provide a radially deployed basket, into which the stone issnagged. Removal of the stone is dependent upon the successfulengagement of the calculus within the body of the device, so that thecalculus is substantially enclosed within the basket. The devicesrequire manipulation of the deployed basket, to ensnare the stone forremoval. Stone removal is directly related to the ability of theoperator to snag the stone with the basket. In contrast, the surgicalscreen traverses the diameter of a duct, and the inserted end of thecatheter remains near the perimeter of duct. Using a device of thisinvention, the stone does not have to be caught within the screen, butis removed at the surface of the screen as the catheter and screen arewithdrawn from the duct. This provides more control and requires lessmanipulation than prior art devices. The devices of this invention aretherefore less likely to damage duct walls during stone withdrawal thanthose of the prior art. Devices of this invention are retractable backinto the housing for withdrawal, if desired.

Similar numbers refer to similar function throughout the Figures. TheFigures are drawn for clarity and are not drawn to scale.

FIG. 4-1 shows (1a) the introduction of a surgical screen housing 10, inthis case a catheter, into the occluded duct 15; (1b) placement of thedistal end 17 of the housing beyond the calculus 20a; (1c) deployment ofthe surgical screen 25; and (1d) fragments 20b of the calculus 20a. Thecalculus fragments 20b can be retracted from the duct with thewithdrawal of the catheter housing 10. In an alternative embodiment (notshown) the calculus 20a is retracted from the duct withoutfragmentation.

The surgical screen, when expanded, will have a diameter substantiallysimilar to the inside diameter of the duct being cleared. For example,when used within a ureter, the diameter of the surgical screen will befrom about 1 mm to about 1 cm. When used within a bile duct, thediameter of the surgical screen will be from about 1 mm to about 1 cm.When used within a blood vessel, the diameter of the surgical screenwill be from about 1 mm to greater than about 5 cm. When used to removea tissue mass which is not within a duct, the surgical screen will befrom about 1 mm or smaller to about 8 cm or greater. The preferreddiameter of the surgical screen will vary with the specific applicationand with the specific anatomy of the patient. In general, the diameterof a surgical screen will be from about 1 mm or less to about 5 cm orgreater, more generally from about 2 mm to about 3 cm.

The housing 10 is preferably an elongate sheath, having an axial boretherethrough. The housing 10 can be flexible or rigid, and the rigiditycan vary by region. Standard catheters and laparoscopic devices wellknown to the art are appropriate. The axial bore is sized to receive thesurgical screen 25 in a constrained configuration. The axial bore opensto the environment at the inserted deployment end 17. Opposite theinserted deployment end 17 is the actuator end (not shown). The actuatorend can include rings, knobs or ridges, for example, for ease ofintegration with a separate actuator means (not shown). Suitableactuator means include slider mechanisms, pistol grip or thumb actuatedmechanisms, scissors handles, and syringe-plunger mechanisms. These andothers are well known to the art. The specific type of actuatormechanism is generally determined by the personal preference of thesurgeon.

The specific configuration and dimensions of the housing will vary withthe use of the device, the parameters of the surgical screen 25, andwhether access for additional laparoscopic or endoscopic devices isprovided. In general the axial bore, into which the surgical screen isconstrained, will have an internal diameter of from less than about 1 mmto about 2 cm or greater.

The outer diameter of the housing 10 will vary with the application andthe size of the expandable screen. The housing in an endoscopic devicewill have a diameter of from less than about 0.7 mm to about 4.5 cm orgreater. The length of endoscopic devices will be from less than about10 cm to about 3 meters or greater. The housing in a laparoscopic devicewill have a diameter of from less than about 3 mm to about 1.5 cm orgreater. The length of laparoscopic devices will be from less than about5 cm to about 20 cm or greater.

The end of the surgical screen housing possesses sufficient lateralintegrity that it is not significantly deformed by the pressure exertedby the constrained surgical screen. When an endoscopic device of thisinvention functions as a catheter and there is little lateral support inthe main body of the catheter, the inserted end of the catheter mayrequire reinforcement to provide consistent constraint of the surgicalscreen element. For example, the surgical screen of this invention canbe delivered to the operative site using the instrument channel, orworking channel, of standard endoscopic devices. Such standardendoscopic devices may also include other devices, especially a laser,lithotripter, visualization means, or crushing stone basket in separatelumina. In a device having a rigid housing, such as a laparoscopicdevice, the inserted end of the housing can have the same physicalattributes as the remainder of the body of the housing.

As shown in FIG. 4-2, the surgical screen is moveable between a firstposition (FIG. 4-2a) wherein the screen is constrained within thehousing and assumes a constrained shape, and a second position (FIG.4-2b, FIG. 4-2c and FIG. 4-2d) wherein the screen means extends past thedistal deployment end and assumes an expanded memory shape. In theexpanded memory shape the screen means acts as a surgical screen. Afteruse, the surgical screen and the housing are removed from the patient.If desired, the surgical screen can be removed in its expanded memoryshape, simultaneously removing, for example, calculi or residualcalculus fragments. Alternatively, the surgical screen is retracted intothe housing, assumes a constrained shape, and is replaced within theaxial bore before the constrained surgical screen and the housing areremoved from the patient. This method can be used when residual calculusfragments, for example, have been removed by irrigation and/oraspiration.

FIG. 4-2 shows a longitudinal cross sectional view of a tasseledsurgical screen. As FIG. 4-2a shows, the housing 110 maintains theconstrained surgical screen 112 in a compressed configuration. Attachedto the constrained surgical screen 112 is a connecting means 114. Theconnecting means 114 can be, for example, a bar, flexible wire, sheath,and the like. If a guide wire is to be used, the connecting means 114can include a lumen for placement of the guide wire. Alternatively, aguide wire can be introduced using a separate lumen. The connectingmeans 114 connects the surgical screen to the remote means (not shown)which project, retract, or rotate the surgical screen relative to thedistal deployment opening. FIGS. 4-2b, 4-2c, and 4-2d show the expandedsurgical screen 125 in various degrees of deployment. By varying theamount of deployment, and thus the diameter of the surgical screen, d,the operator can maximize the screening effects of the surgical screenwhile minimizing potential damage to the duct wall due to surgicalscreen expansion, or due to the withdrawal of the expanded screen fromthe body.

FIG. 4-3 shows one embodiment of a surgical screen 225 of thisinvention. Three elastic strips or wires form concentric loops in theirexpanded configurations. These strips or wires form a surgical screen225 suitable for removal of entire calculi, or of calculus fragments. Itwill be obvious to one skilled in the art that while three loops whichare curved along their length are pictured, other configurations arealso appropriate for use with this invention. One, two, four, or moreloops can be used. The loops can be fairly regular (as shown), or theycan be eccentric, scalloped, rounded, oval or irregularly shaped. Thedegree of longitudinal curvature, and curvature across the width of thescreen, can be varied to suit the desired application. The loops can bespaced relatively widely, especially where an unfragmented calculus isto be removed, or they can be spaced fairly closely together, especiallywhere a calculus is to be fragmented and/or calculus fragments are to beremoved. A perforated sheet can be suspended across a loop of amultiloop surgical screen, similar to the configuration shown in FIG.4-5. Alternatively, a perforated sheet can be suspended between any twoloops of a multiloop surgical screen (not shown).

FIG. 4-4 shows a side view of a tasseled surgical screen 225 of thisinvention. Enlargements show various end treatments for the tassels.Pictured are (a) an elastic wire which terminates in a serf-closingloop; (b) an elastic wire that terminates in a blunted or truncated end;(c) an elastic wire that terminates in a knob of added material, such asa plastic; and (d) an elastic wire that terminates in a knob formed ofthe elastic material itself. Each individual strand which makes up atassel filter can be substantially straight along its length, or it canbe curved, wavy, or undulating in two or three dimensions. The strandscan be substantially similar in configuration, or they can be different.

FIG. 4-5 shows a surgical screen which includes an elastic loop 236, anelastically deformable ring or loop of elastic material, which isspanned by a barrier material 234. The elastic loop 236 is preferablypseudoelastic, and more preferably a shape memory alloy. As shown, aconnector 228 can be used to orient the surgical screen sharply acrossthe duct. The pictured connector 228 is an extension of the elastic loop236. Alternatively, the connector 228 can integrate with, but beseparate from the elastic loop 236.

The diameter of the elastic loop 236 will vary with the diameter of ductfor which it is intended, as discussed above. The depth of arc describedby the barrier material 234 when suspended from the memory loop is fromless than about 1 mm to about 1 cm or greater. The surgical screen canprovide a sack-like structure which substantially encloses a calculus.The calculus can then be removed without fragmentation, or it can befragmented. If the calculus is fragmented, the pieces can be removedwithin the surgical screen, they can be aspirated or irrigated from theface of the surgical screen, or the surgical screen can be retracted andthe fragments can be-washed from the site by normal duct fluid flow.

The barrier material is a flexible and biocompatible material. Whenconstrained, the barrier material 234 is collapsed and furled around theconstrained elastic loop 236. The barrier material is sufficiently thinthat it can be folded, furled, or gathered, together with the elasticloop 236, to fit within the housing. The composition of the barriermaterial will reflect the specific use of the surgical Screen. In oneembodiment the barrier material is substantially permeable to fluids. Insuch an embodiment, the barrier material is a web, net or grid,perforated sheet, and the like, and is substantially permeable to bodyfluids and other liquids, such as normal saline solution or gases, whichmight be present during surgical procedures. Suitable materials includenylon or dacron netting or screen, or a grid of elastic material.

The surgical screen is compressed and loaded within the housing. In thisconstrained configuration, the screen device can be sterilized, packagedand stored for later use. The screen device (i.e., surgical screen andhousing) is preferably a disposable device.

In one preferred embodiment, a device of this invention comprises (a) ahousing having a distal deployment opening; (b) a surgical screen whichis constrainable within the housing, the surgical screen comprising anelastic material; and (c) remote means to project, retract and/or rotatethe surgical screen relative to the distal deployment opening; thesurgical screen being moveable between a first position wherein thesurgical screen is constrained within the housing, and a second positionwherein the surgical screen is extended past the distal deployment endand assumes an expanded shape.

A device of this invention can be used in a variety of procedures, suchas the capture an undesired mass from within a duct. For example, adevice of this invention can be used to remove a gallstone from the bileducts; to remove a kidney stone from the urinary system; or to remove anembolus from a blood vessel. A surgical screen of this invention can beused during an operative or surgical procedure, to contain or hold adiscrete tissue body for further procedures or for removal. For purposesof example only, and not as a limitation, reference will be methods forremoval of a calculus from a ureter, wherein the device housing is acatheter. It is to be understood that this is for simplicity of exampleonly, and that the apparatus, methods and teachings will be similarlyapplicable a variety of such uses.

In one method, the deployment end of a housing containing a surgicalscreen is partially inserted into a human or animal patient. A guidewire may or may not be used for placement of the device. When a guidewire is used, it is introduced into the ureter and placed appropriately,e.g., beyond an obstruction. A catheter is slipped over the guide wire.The guide wire is then removed, and the surgical screen is extendedbeyond the deployment end of the catheter. The guide wire preferablypasses through a separate lumen in the catheter. Alternatively, theguide wire can pass through the catheter lumen which houses the surgicalscreen, in which case the connecting means can be tubular and provide aninternal bore to accept the guide wire. Alternatively, the guide wirecan pass through the axial bore of the housing adjacent the connectingmeans, or the guide wire can be introduced through a bore or slot withinthe connecting means. The surgical screen can be radiopaque for ease ofplacement at the operative site.

A method for removing an internal obstruction comprises (a) inserting anend of an elongate housing, such as a catheter end, beyond a mass, suchas a calculus; (b) deploying a surgical screen from the housing end; and(c) retracting the housing and surgical screen to remove the mass.Alternately, the calculus can be fragmented before removal. Calculusfragmentation can be by, for example, lithotripsy (ultrasound),mechanical fragmentation, or laser fragmentation. This method comprises(a) inserting a catheter end beyond a mass; (b) deploying a surgicalscreen from the catheter end; (c) fragmenting the mass; and (d)retracting the catheter and surgical screen to remove mass fragments.

Yet another method of this invention comprises (a) inserting a catheterend beyond a mass; (b) deploying a surgical screen from the catheterend; (c) fragmenting the mass; (d) removing mass fragments from theoperative site; (e) retracting the surgical screen into the catheter;and (f) removing the catheter. The use of this method prevents calculusfragments from migrating from the fragmentation site where they cannotbe retrieved and can act as nucleation sites for further obstructions.Fragments of the obstructing mass which remain can be removed, forexample, by flushing the operative site with normal saline or otherliquids, by aspiration of the fragments, by mechanical means, or by acombination of means.

As a separate embodiment of this invention, it has been discovered thatstone baskets of the prior art can be advantageously made of a shapememory alloy, preferably a pseudoelastic shape memory alloy, and morepreferably a superelastic shape memory alloy. The attributes of, andprocesses for obtaining, such shape memory alloys have been discussedabove.

Stone baskets use a trap, or cage, effect. They facilitate passage ofthe obstruction (e.g., a calculus or other mass) inside the basket, butthen prevent escape of the obstruction when it is in place in thebasket. The basket and obstruction are then withdrawn. Prior art stonebaskets include baskets of helically deployed wires (U.S. Pat. No.4,347,846, to Dormia), baskets of flat spring strips (U.S. Pat. No.4,590,938 to Segura et al.), baskets which facilitate the insertion of aprosthesis (U.S. Pat. No. 4,592,341 to Omagari et al.), baskets whichare used to capture and then crush the calculus (U.S. Pat. Nos.4,691,705 and 4,741,335 to Okada, and 4,768,505 to Okada et al.).

Stone baskets generally are classed as medical retriever devices. Theyare adapted for delivery and use through a catheter, or through theworking channel of an endoscope. Stone baskets generally comprise anarrow, elongated sheath; a basket of relatively large diameterextendible from the distal end of the sheath and collapsible whenwithdrawn into the sheath; and a remote means to project, retract,and/or rotate the basket relative to the distal end of the sheath. Thebasket is defined by a multiplicity of spaced apart, outwardly bowedspring arms or wires which extend generally axially from the sheath, andare joined at each of the distal and proximal ends of the basket.

The use of shape memory alloys which exhibit pseudoelasticity in thestone baskets of the prior art allow the use of thinner arms (wires orstrips, as the case may be) in the makeup of a basket having a desiredexpanded diameter, or permit a much greater deformation of the basketupon deployment. This permits the use of catheters or working channelshaving a significantly decreased diameter than those of the prior art.Introduction of a thinner shape memory alloy stone basket catheterbeyond a calculus is easier than introducing the stone basket cathetersof the prior art. The increased diameter and/or thinner wires produce astone basket which is easier to use than those of the prior art. Thethinner wires and/or larger diameter provide more unimpeded area intowhich the blocking calculus can be captured for removal.

In a fifth form of the present invention, a remotely operated device ofthis invention comprises an elongate housing, and a retractor of a shapememory alloy. Remote means are provided to project, retract and/orrotate the retractor means relative to the distal end of the housing.The retractor preferably comprises one or more loops of a shape memorymaterial. The retractor is preliminary constrained within a housing,such as a laparoscope or an endoscope. It is deployed from within thehousing at an operative site. The retractor is generally used tomanipulate organs or other tissues. The retractor can be replaced withinthe housing. The housing is then withdrawn from the patient.

The shape memory retractor means is a strip or wire of a shape memorymaterial which forms one or more loop in the expanded configuration. Allor part of the retractor can be spanned by a semipermeable or permeablemembrane.

A remotely operated device of this invention comprises an elongatehousing having a distal end and a proximal end; a retractor of a shapememory alloy; and remote means to project, retract and, optionally, torotate the retractor means relative to the distal end of the housing.The retractor comprises one or more loops of a shape memory material. Aloop can be substantially round, oval, or shaped like a teardrop, forexample, or it can be eccentric in its shape. When two or more loops arepresent, they can be of similar shape, or they can be dissimilar inshape. Two or more fingers or lobes can be present. One or more loop canbe partially or completely spanned by a membrane. The proximal ends ofthe retractor loop can integrate with, or function as, the remote meansto project, retract and rotate the retractor means relative to thedistal end of the housing.

The retractor is preliminary constrained within the housing. Theretractor is deployed at an operative site, where the retractor is used,for example, to manipulate organs or other tissues. The retractor can bemoved back to the preliminary position, so that the retractor is againconstrained within the housing. The device can then be repositioned andthe retractor redeployed at an alternate site, or the housing can bewithdrawn from the patient.

The operative site can be, for example, a surgical site, biopsy site,the site of diagnostic procedures, and the like. For purposes of exampleonly, and not as a limitation, reference will be made to a housing whichis a catheter. It is to be understood that this is for simplicity ofexample only, and that the apparatus, methods and teachings will besimilarly applicable to devices in which the housing is, for example, alaparoscopic or alternate endoscopic device.

As used herein, the term "retractor" refers to a looped retractor meanswhich is comprised of a shape memory alloy. The retractor is preferablya pseudoelastic shape memory alloy, and most preferably a superelasticshape memory alloy. The shape memory alloy can have a biocompatiblecoating, if desired.

The retractor differs from the prior art in several key aspects. Theelastically compressible retractor material makes use of the property ofshape memory to achieve its desired effect. Materials which aredeformable and which return to a predetermined shape demonstrate shapememory. Spring steel and plastic materials, for example, can demonstrateshape memory. Preferably, the compressible retractor material is a shapememory alloy (SMA) which demonstrates pseudoelasticity when deformedunder an applied stress. Articles made of a pseudoelastic shape memoryalloy can be deformed from an original undeformed configuration to asecond deformed configuration. Such articles revert to the undeformedconfiguration under specified conditions, and are said to have "shapememory."

The use of an SMA which exhibits pseudoelasticity has the advantage thatthe amount of elastic deformation that is available is large comparedwith that available from many other materials. The large amount ofelastic deformation of the elements allows the device to be used to formretractors of relatively large dimension and relatively eccentric shape,while simultaneously ensuring that the device has a small transversedimension when the retractor elements are constrained within a housing,allowing the device to pass through small passages or surgical entrysites.

FIG. 5-1 shows a cross-sectional view of the distal end of a retractordevice of this invention. The retractor 8 is constrained within thehousing 10. The distal (inserted) deployment end 12 is shown. Remotemeans to project and retract, and optionally to rotate, the retractor islocated at the proximal end of the device (not shown), and is in thedirection of the arrow. The housing 10 is preferably an elongate sheath,having an axial bore 14 therethrough. Standard catheters, endoscopic andlaparoscopic devices well known to the art are appropriate. The axialbore 14 is sized to receive the retractor 8 in a constrainedconfiguration. The axial bore 14 opens to the environment at thedeployment end 12.

The specific configuration and dimensions of the housing will vary withthe use of the device, the parameters of the operative site, the size ofthe retractor, the mass of tissue or the prosthetic device which is tobe manipulated, and whether access for additional laparoscopic orendoscopic devices is provided within a retractor device. In general theaxial bore 14, into which the retractor is constrained, will have aninternal diameter of from less than about 1 mm to about 2 cm or greater.The outer diameter of the housing 10 will vary with the application, thediameter of the axial bore, and whether access for additional oralternate instruments is provided within the housing. For example, thehousing in an endoscopic device will have a diameter of from less thanabout 0.7 mm to about 4.5 cm or greater. The length of endoscopicdevices will be from less than about 10 cm to about 3 meters or greater.The housing in a laparoscopic device will have a diameter of from lessthan about 3 mm to about 1.5 cm or greater. The length of laparoscopicdevices will be from less than about 5 cm to about 30 cm or greater.

The end of the retractor device possesses sufficient lateral integritythat it is not significantly deformed by the pressure exerted by theconstrained retractor. The housing 10 may be rigid or flexible, and itsrigidity can vary along its length. When an endoscopic device of thisinvention functions as a catheter, and there is little lateral supportin the main body of the catheter, the inserted end of the catheter mayrequire reinforcement to provide consistent transverse compression ofthe retractor element. A retractor of this invention can be delivered tothe operative site using the instrument channel, or working channel, ofa standard laparoscopic or endoscopic device. Such a standard device mayalso include other devices, especially a cautery device, laser,lithotripter, visualization means, scalpel means, and the like, in oneor more separate lumina.

FIG. 5-2 shows a top view of an expanded retractor of this invention.The retractor 108 has three loops 116 which fan out from the housing 110upon deployment. One or more of the loops can be spanned by a membrane(see FIG. 5-4). While three loops are shown, it will be apparent to oneskilled in the art that one, two, four, or more loops can be provided toform the retractor. While the loops 116 pictured are substantiallydrop-shaped, other configurations are easily imagined. The loop or loops116 can be, for example, round, oval, triangular, square, rectangular,irregularly shaped, and the like. When two or more loops are present theloops can be substantially similar in shape, or they can be dissimilarin shape.

The loops 116 can overlap, or they can be be substantially independentfrom one another. In such a case a deforming pressure placed upon oneloop perpendicular to the general plane of the loop will deform thatloop, but will not affect the other loops. In a preferred embodiment,the loops 116 are interconnected and/or overlapping, and a deformingpressure placed upon one loop perpendicular to the general plane of theloop will be transmitted to the other loops. All loops thus acttogether, providing strength across the width of the retractor. Theloops can be coated with a biocompatible material. The coated oruncoated loops can have a surface that prevents slippage of theretracted tissue. For example, the biocompatible coating can provide aroughened or non-slippery texture to the loops. Alternatively, the loopscan have gentle edges or serrations upon all or part of the exposedsurface.

FIG. 5-3 shows a top view of an expanded retractor of this invention.This preferred retractor 108 has three lobes, or finger means 118 whichfan out from the housing 110 upon deployment. One or more of the fingermeans can be spanned by a membrane (see FIG. 5-4). Alternatively, one ormore of the spaces between fingers can be spanned by a membrane (seeFIG. 5-5).

FIG. 5-4 shows a top view of another expanded retractor of thisinvention. This retractor 108 has one loop means 116 which expands upondeployment from the housing 110. As shown, the loop is spanned by apermeable, semipermeable or substantially impermeable membrane 120. Themembrane 120 is preferably made of a flexible and impermeablebiocompatible material. The membrane is sufficiently thin that it can befolded or gathered, together with the elastically deformable retractormeans 108, to fit within the housing 110. Suitable membrane materialsinclude sheets of polyethylene, polyvinyl chloride, urethane, siliconerubber, and the like.

In an alternative embodiment, the membrane 120 is substantiallyimpermeable to tissue, but is generally permeable to body fluids andother liquids which might be present during surgical procedures. In thisembodiment, the membrane 120 can be a grid of shape memory material, anet, a web, and the like. Suitable materials include perforated, webbedor netted polyethylene, polyvinyl chloride, urethane, silicone rubber,and the like.

FIG. 5-5 shows a top view of yet another expanded retractor of thisinvention. This retractor 108 has two lobes, or finger means 118 whichfan out upon deployment from the housing 110. The space between thefingers is spanned by a membrane 120.

FIG. 5-6 shows a top view of an alternate expanded retractor of thisinvention. Emerging from the housing 110 is a retractor 108 which hastwo loops 116. As shown, a smaller loop 116a is nested within a largerloop 116b. In the pictured embodiment, the smaller loop 116a is spannedby a membrane 120. It will be apparent to one skilled in the art thatany number of such loops, in various configurations, whether or notspanned by a membrane 120 either across or between loops, can beprovided to form the retractor.

FIGS. 5-7 through 5-11 show side views of a deployed retractor of thisinvention.

FIG. 5-7 shows a side view of a deployed retractor of this invention.The amount of elastic curvature of the retractor 208 is greatest at thebase of the retractor, where the retractor emerges from the housing 210.

FIG. 5-8 shows an alternate side view of a deployed retractor of thisinvention. The amount of elastic curvature of the retractor 208 isfairly consistent across the length of the retractor 208.

FIG. 5-9 shows yet another side view of a deployed retractor of thisinvention. The retractor 208 has the smallest radius of curvature at itsdistal end.

In FIG. 5-10, the retractor 208 is substantially straight upondeployment from the housing 210.

FIG. 5-11 shows a retractor 208 which is gently curved.

FIGS. 5-12 and 5-13 show alternate end views of an expanded(unconstrained) retractor, such as shown by arrow E in FIG. 5-10. In endview, the expanded retractor can be flat. However, using the shapememory material retractors of this invention, other configurations arepossible. FIG. 5-12 shows a retractor which is gently curved across itswidth. FIG. 5-13 shows a retractor 308 which is asymmetrical: it isflattened on one side, and curved or hooked on the other side. Theseconfigurations find particular application when the mass to be gentlymanipulated by the retractor is substantially parallel to the length ofthe retractor device or retractor housing. As used herein, the term"mass" refers to a tissue mass, or to a prosthetic device. Otherconfigurations in addition to the flattened silhouette, and the curvedconfigurations shown in FIGS. 5-12 and 5-13, will be readily apparent toone skilled in the art. For example, the retractor may be sharplyangled, or it may be twisted along its length. The retractor may alsohave curvature in two or more directions in any of the planes described,such that the retractor may have a zig-zag or undulating appearance.

The various embodiments shown in FIGS. 5-2 through 5-13 can be combinedas desired. A retractor of this invention can comprise, for example, thethree-fingered shape of FIG. 5-3, curved along its length as shown inFIG. 5-8, and curved along its width as shown in FIG. 5-12. Such aretractor is generally cup-shaped.

FIGS. 5-14 and 5-15 show alternate cross-sectional views of aconstrained retractor, taken at line a--a of FIG. 5-1. FIG. 5-14 shows aretractor made of wires 408 having a circular cross section, theretractor being constrained within the housing 410. FIG. 5-15 shows aretractor of strips 408 having an oval cross section. It will be clearto one skilled in the art that many other wire or strip cross-sectionsare equally appropriate for use in the retractors of this invention. Forexample, the retractor can be made of a strip member which is squared,rectangular, triangular, and the like. A cross-section such as the ovalshape of FIG. 5-15 is generally preferred for the retractors of thisinvention. Such a cross-section provides strength upon the applicationof force which is perpendicular to the general plane in which theretractor is elastically deployed, but provides minimized dimensions andresistance upon constraint of the retractor within the housing 410.

In one preferred embodiment, a device of this invention comprises (a) ahousing having an axial bore with a distal deployment opening; (b) aretractor which comprises a loop shape, the retractor beingconstrainable within said axial bore, and the retractor comprising ashape memory alloy; and (c) remote means to project and retract, and,optionally, to rotate, said retractor relative to the distal deploymentopening. The retractor is moveable between a first position wherein theretractor is housed within the axial bore and assumes a constrainedshape, and a second position wherein the retractor is extended past thedistal deployment end and assumes an expanded memory shape.

The retractor is compressed and loaded within the housing. In thisconstrained configuration, the retractor device can be sterilized,packaged and stored for later use. The retractor device (i.e.,retractor, housing, and deployment means).is preferably a disposabledevice. When needed, the surgeon visually assesses the size of retractornecessary for tissue manipulation, and selects a retractor which has anappropriate diameter, curvature and/or membrane.

In use, the device is partially inserted into a human or animal patientand used to manipulate organs or other tissues at an operative site. Aguide wire may or may not be used for placement of the device. When aguide wire is used, it is introduced into the operative site and placedappropriately. A catheter containing a retractor is slipped over theguide wire. The guide wire is then removed, and the retractor isextended beyond the deployment end of the catheter. The guide wirepreferably passes through a separate lumen in the catheter.Alternatively, the guide wire can pass through the catheter lumen whichhouses the retractor. The retractor can be radiopaque for ease ofidentification and use at the operative site.

A sixth form of the present invention provides a sheath-protected bladewherein the sheath is substantially straight. When it is constrainedwithin the sheath, the blade is substantially linear. Upon deploymentfrom the sheath, the blade is unconstrained, and assumes a configurationwhich is elastically deflected away from the longitudinal axis of thesheath. The blade is an elastically deformable material, preferably apseudoelastic material, and more preferably a shape memory alloy.

One or more exposed edge of the elastic blade can provide a cuttingedge. Exposed surfaces which are blunted can provide a means formanipulation of tissues or artificial devices.

A remotely operated device of this invention comprises an elongatehousing, and an elongate blade which can be linearly constrained withinthe housing. The elastic blade is deployable from within the housing,and assumes a curved unconstrained shape upon deployment. Remote meansare provided to project and retract, and optionally to rotate, theelastic blade relative to the distal end of the housing. Alternatively,remote means are provided to project and retract the sheath relative tothe elastic blade.

The sheathed blade device of this invention differs from the prior artin several key aspects. The sheath is substantially straight along itslength. When constrained within the sheath, the elastic blade is alsosubstantially straight along its length. When deployed from the sheaththe elastic blade assumes, as much as possible, its curved unconstrainedshape.

The blades of this invention are curved (e.g., curled or twisted) alongtheir length to a greater or lesser degree. The degree of curvature canbe consistent along the length of the blade, or the curvature can varyin degree and/or in direction. A cutting surface can be provided at anydesired exposed edge of the blade. When the unconstrained shape of theelastic blade is generally semicircular (such as shown in FIG. 6-8) acutting surface can be provided along the sides of the blade (such asshown in FIGS. 6-13, 6-14, and 6-19). Alternatively, a cutting surfacecan be provided at the tip of the blade (such as shown in FIGS. 6-15,6-16, and 6-17) to provide a scalpel which has a cutting surfacedirected 180° from the opening of the sheath. Varying the amount ofdeployment of the blade varies the cutting angle, so that a blade can beprovided in which the cutting surface is angled from 0° to 180° orgreater from the axis of the sheath.

The elastic nature of the blade allows for a complete retraction of theblade into the sheath for a complete protective enclosing of the blade,protecting both the blade and the body tissue during both the insertionand removal of the instrument. The sheath not only protects the bladebut also guides and directs the blade whereby the extension of the bladefrom the sheath can comprise a cutting movement of the blade, ratherthan merely a means for exposing the blade for subsequent manipulation.The user, upon selection of the appropriate elastic blade (i.e., a bladehaving a desired curvature and position of cutting edge), orients thesheath, and then extends the blade. The blade is extended either bymoving the blade outward from the sheath, or retracting the sheathrelative to the blade.

Similar numbers refer to similar function throughout the Figures. TheFigures are drawn for clarity and are not drawn to scale.

FIG. 6-1 is an external view of a device of this invention. The housing10 is an elongate member, having an axial bore therethrough. The housinghas a distal end 12, which acts as a sheath for the elastic blade, and aproximal end 14, which provides integration with a means to project andretract the elastic blade relative to the distal end of the housing 10.Between the distal end 12 and the proximal end 14 is the housing body16.

The housing preferably also includes a remote means 18, the actuation ofwhich causes the elastic blade to be deployed from the housing, or thehousing to be retracted from the blade. The remote means 18 can beactuated by any manual or motorized means (not shown). In oneembodiment, as pictured, two finger rings 20 are part of the proximalend 14. An additional thumb ring 22 is part of the remote means 18. Whenthe thumb ring 22 is depressed, the elastic blade (not shown) isdeployed from the housing at the distal end 12. The pictured rings arefor ease of handling. Alternatively, knobs or edges, for example, can beprovided for ease of integration with a separate actuator means (notshown). Separate actuator means include slider mechanisms, pistol gripor thumb actuated mechanisms, scissors handles, and pistol-gripmechanisms. These and others are well known to the art. The specifictype of actuator mechanism is generally determined by the personalpreference of the surgeon. The orientation of the blade relative to theactuator mechanism can be configured to suit the specific application orthe preference of the surgeon.

The distal end 12 of the housing acts as a sheath which constrains theelastic blade in a substantially linear configuration. It possessessufficient lateral integrity that it is not significantly deformed bythe pressure exerted by the constrained elastic blade. When anendoscopic device of this invention is a catheter and there is littlelateral support in the housing body 16, the distal end 12 of thecatheter may require reinforcement to provide consistent constraint ofthe elastic blade (not shown). In a device having a rigid housing, suchas a laparoscopic device, the distal end 12 of the housing can have thesame physical attributes as the remainder of the housing. Standardendoscopic and laparoscopic devices well known to the art areappropriate for use with the elastic blades of this invention.

The housing body 16 of a device which is used in laparoscopy must havesufficient structural integrity that it is easily inserted through asurgical opening into the body of the patient without undue deformation.Materials with sufficient structural rigidity include stainless steeland rigid polymeric materials such as plastics. The material of theproximal end of the housing 14, the material of the housing body 16, andthe material of the distal end 12, can be the same, or can havedifferent physical properties. For example, the housing body 16 used inendoscopic surgery will generally be flexible, to allow insertionthrough naturally occurring orifices, ducts, and/or passages, or toallow insertion through the working channel of an endoscope. Suitablepolymeric material includes polytetrafluorethylene, polyurethane,polyethylene, teflon, and the like. The material of such a flexiblehousing may be reinforced at the distal end 12 with fibers, rings, orlongitudinal ribs, for example, to enable it to withstand the forcesexerted on it by the elastic blade while it is constrained within, anddeformed by, the housing.

The specific configuration and dimensions of the housing 10 will varywith the use of the device, the parameters of the elastic blade, andwhether access for additional laparoscopic or endoscopic devices isprovided. The housing 10 can be substantially uniform along its length,as shown in FIG. 6-1, or it can vary in diameter or shape, as shown inFIG. 6-4. Preferably, the housing 10 has a circular cross-section. Acircular cross-section permits delivery of an elastic blade of thisinvention through a standard laparoscopic trocar, or through theinstrument channel of a standard endoscope. However, othercross-sections may be preferable, for example, to adapt an endoscopicdevice to the orifice through which it will enter the body.

In general, the housing in an endoscopic device will have an outsidediameter of from less than about 0.7 mm to about 4.5 cm or greater. Thelength of endoscopic devices will be from less than about 10 cm to about3 meters or greater. The housing in a laparoscopic device will have anoutside diameter of from less than about 0.3 mm to about 1.5 cm orgreater. The length of laparoscopic devices will be from less than about5 cm to about 30 cm or greater.

FIG. 6-2 and FIG. 6-3 are alternate cross-sectional views of a device ofthis invention, the cross section being taken vertically along thelongitudinal axis of the distal end 12 of FIG. 6-1.

FIG. 6-2 shows the distal end 112 of a housing 110 which is made as oneunit. An axial bore 130 runs axially through the housing. At theproximal end 132 of the axial bore 130, the axial bore can have anyconvenient size and shape. In general the axial bore will have aninternal diameter of from less than about 0.5 mm to about 2 cm orgreater. At the distal end, the axial bore becomes flattened, and formsthe sheath bore 134 for the constrained elastic blade 136. The sheathbore 134 is sized to slidably accept the constrained elastic blade 136,and to constrain the elastic blade 136 in a substantially linearconfiguration. When the elastic blade 136 is fully housed within thesheath bore 134, the sheath bore 134 contains at least those portions ofthe elastic blade 136 which have cutting edges. Preferably the cuttingedges of the elastic blade 136 do not touch or rub against the sheathbore 134 when stored, or upon deployment or retraction, as such contactcan dull the cutting edges.

In general the proximal end 132 of the axial bore 130 will be circularand relatively large, to facilitate the loading of the connecting means138 and the elastic blade 136 within the sheath. A circular conformationis for general ease of manufacture and handling, and alternateconformations can be used, as desired. The proximal end 132 of the axialbore 130 houses the connecting means 138. The connecting means 138 canbe, for example, soldered or otherwise affixed to the elastic blade.Alternatively, it can be a continuation of the elastic material used toform the elastic blade 136.

FIG. 6-3 shows the distal end 112 of a housing 110 which is made as twounits. One unit is a tube 140 through which extends an axial bore 130. Abushing 142 is fitted within the tube, for example by press fit or bythread. The bushing 142 provides the sheath bore 134 for the constrainedelastic blade 136. The bushing 142 can be made of any suitable material,polymeric and/or metallic. It may be desirable to pass an electriccurrent through the elastic blade 136, so that the elastic blade 136acts as an electrocautery device. In such an embodiment the bushing canbe a non-conducting polymer, and it can act to keep the elastic blade136 electrically insulated from the housing 110. The elastic blade 136is held for reciprocal motion by the connecting means 138.

FIG. 6-4 is an alternate cross-sectional view of the distal end 112 of ahousing 110 of this invention, the cross section being taken verticallyalong the longitudinal axis. In this embodiment the housing 110 is ametal or plastic tube which has been flattened at one end. The flattenedend provides the sheath bore 134 in which the elastic blade is slidablyconstrained. The elastic blade 136 is held for reciprocal motion by theconnecting means 138.

If the housing 110 is a tubular structure having a flattened end, asshown in FIG. 6-4, it may be desirable to provide a covering of anysuitable material (not shown). The covering provides a uniform outerdimension for the device. A covering which provides a substantiallyuniform circular cross-section is advantageous if the blade device is tobe introduced into the body through a standard laparoscopic trocar, orthrough the instrument channel of a standard endoscope. The coveringacts to minimize the escape of fluids (either liquid or gas) from thebody. The covering can be made of a polymeric material such aspolyurethane, polyethylene, and the like.

FIG. 6-5 is a cross-sectional view of the device of FIG. 6-2 takenacross the longitudinal axis at line b--b. The housing 210 surrounds theaxial bore 230. Within the axial bore is the connecting means 238. Theconnecting means 238 can have any suitable cross-sectional shape. In theshown embodiment the connecting means 238 spans axial bore 230 tominimize lateral motion as the sheath and elastic blade (not shown) aremoved longitudinally relative to each other. If an electric current ispassed through the connecting means 238 and the elastic blade, so thatthe elastic blade acts as an electrocautery device, it may be desirableto include a layer of a non-conducting material (not shown) aroundconnecting means 238 to insulate the connecting means 238 from thehousing 210.

FIG. 6-6 is a cross-sectional view of the device of FIG. 6-2 takenacross the longitudinal axis at line c--c. The housing 210 surrounds thesheath bore 234. Within the sheath bore is the elastic blade 236.

One or more edges of the elastic blade 236 can remain dull, and can aidthe non-cutting manipulation of tissues or artificial devices duringsurgery. For instance, the blade can have no cutting edges. Thisminimizes the amount of trauma to surrounding tissues upon manipulationof the blade. More generally, the elastic blade 236 has one or moresharpened edges 240. The sheath bore 234 is substantially flattened, andholds the elastic blade 236 so that the elastic blade 236 is constrainedlinearly. In a preferred embodiment, the sheath bore 234 is slightlyenlarged in the region of the sharpened edges 240. This acts to protectthe sharpened blade from wear as it is deployed from, and withdrawninto, the housing. Alternatively, the sheath bore 234 closely mimics theouter shape of the elastic blade 236. Other embodiments are alsopossible, such as a sheath bore 234 which is substantially rectangularor eccentric, and such embodiments will be readily apparent to oneskilled in the art.

FIG. 6-7 is a cross-sectional view of a cutting edge of a cutting bladeof this invention. A cutting edge can be provided at any edge of theelastic blade. In a preferred embodiment, the edge of the elasticmaterial is beveled, and provides a cutting blade. FIG. 6-7 shows acutting edge which is beveled on both sides. The bevel or bevels can beat any appropriate angle from the plane of the blade. When two bevelsare present, they can have the same angle of bevel, or different anglesof bevel. In FIG. 6-7, the bevels are β and φ degrees from the plane ofthe blade. Alternatively, only one bevel may be present (not shown). Thehoning of an edge to form a cutting blade is well known in the art. Ifdesired, the cutting blade can be serrated. The cutting edge ispreferably derived from the beveled elastic material itself. However, itmay be desirable or necessary to provide a honed blade edge to theelastic material. This additional blade can be added mechanically, asshown in FIG. 6-12. Alternatively, two or more elastic materials can beused to form the blade. For example, a non-cutting elastic blade can becombined with an elastic alloy blade having a cutting edge.

FIG. 6-8 through FIG. 6-11 are side views of the device of FIG. 6-1 whenthe elastic blade is deployed. A cutting surface can be provided at anydesired exposed edge of the blade.

FIG. 6-8 shows an elastic blade 336 which is substantially semicircularupon deployment from the housing 310. The degree of curvature can besubstantially consistent along the length of the blade, as shown, or thecurvature can vary, i.e., the elastic blade can have a uniform ornon-uniform radius of curvature.

FIG. 6-9 shows an elastic blade 336 which describes an S-shaped curveupon deployment from the housing 310.

FIG. 6-10 shows an elastic blade 336 which is twisted along itslongitudinal axis upon deployment from the housing 310. The elasticblade is shown having a clockwise spiral, but counterclockwise spirals,and combinations of the two, are also appropriate for use herein.

FIG. 6-11 shows an elastic blade 336 which is sharply curved in theregion closest the housing 310, and substantially linear in the regionfurthest from the housing 310.

FIG. 6-12 shows a standard surgical blade 350, which is attached to astrip of elastic material 352 by a mechanical means 354. The standardsurgical blade 350 is not curved. However, the strip of elastic material352 is strongly bent, and upon deployment from the housing it acts tobend the surgical blade 350 sharply away from the housing 310.

FIGS. 6-13 through 6-19 are each a top view of an alternate elasticblade of this invention.

FIG. 6-13 shows a top view of an elastic blade 436 which has onelongitudinal sharpened (cutting) edge 460.

FIG. 6-14 shows a top view of an elastic blade 436 in which the entireperimeter of the blade provides the sharpened edge 460.

FIG. 6-15 shows a top view of an elastic blade 436 in which only themost distal surface provides the sharpened edge 460.

FIG. 6-16 shows a top view of an elastic blade 436 in which only themost distal surface provides the sharpened edge 460. The sharpened edge460 has two angled sections, 460a and 460b, each of which is angledrelative to the longitudinal axis of the blade. The angled sections canhave any desired degree of angle relative to the longitudinal axis ofthe blade, and the degree of angle for each section can be similar to,or dissimilar to, that of the other section.

FIG. 6-17 shows a top view of an elastic blade 436 in which an outwardlycurved surface provides the sharpened edge 460.

FIG. 6-18 shows a top view of an elastic blade 436 in which an inwardlycurved surface provides the sharpened edge 460.

FIG. 6-19 shows a top view of a preferred embodiment of the elasticblade 436 in which the distal perimeter of the blade provides thesharpened edge 460, and the proximal edges of the blade are unsharpened.The width of distal section of the elastic blade 436 is somewhat lessthan the width of the proximal section. The distal portion of theelastic blade having the sharpened edge 460 is narrower than proximalunsharpened portion, so that the sharpened edge 460 will not touch thesides of the sheath bore. The sharpened edge 460 is therefore protectedduring the process of deployment and retraction of the elastic blade436.

FIG. 6-20 shows a top view of an embodiment of the elastic blade 436 inwhich all edges of the blade are unsharpened. This embodiment ispreferred when the blade is not used to cut tissues, and can function tomanipulate tissues or artificial devices.

The elastic blade is compressed and loaded within the sheath. In thisconstrained configuration, the blade and sheath can be sterilized,packaged and stored for later use.

In one preferred embodiment, a device of this invention comprises (a) ahousing having a distal deployment opening; (b) a curved elastic bladewhich is linearly constrainable within the housing; and (c) remote meansto project and retract the elastic blade relative to the distaldeployment opening; the elastic blade being moveable between a firstposition wherein the elastic blade is linearly constrained within thehousing, and a second position wherein the elastic blade is extendedpast the distal deployment end and assumes a memory shape.

In a preferred embodiment, a blade of this invention comprises anelastically deform able curved blade.

According to a seventh form of the present invention, it has now beendiscovered that a pivoted two-bladed device, such as a forceps,scissors, snips, and the like, can be combined with an elasticallydeformable stem. Remote blade actuator means are used to cause theblades to splay apart or come together. An elastic member and aconstraining member, for deforming the elastically deformable stem, arepresent. The elastic member and the constraining means arelongitudinally slidable relative to one another, causing the angulardeformation of the elastically deformable stem.

The elastically deformable stem includes an elastic member which issubstantially linear when it is constrained, and assumes a substantiallynon-linear shape when it is unconstrained. When a constraining elongatehousing is present and serves as the constraining member, the elasticmember is moveable between a first position wherein the elastic memberis linearly constrained within the housing, and a second positionwherein the elastic member is deployed from the housing and isunconstrained. Alternatively, the housing is moveable between a firstposition wherein the elastic member is linearly constrains, and a secondposition wherein the elastic member is unconstrained. The elasticallydeformable stem, which includes the elastic member, assume a nonlinearshape. The amount of deformation of the elastically deformable stem canbe controlled by adjusting the amount of the elastic member which is notconstrained by the elongate housing.

If the device does not include an elongate housing, and in embodimentsin which the elongate housing is present but is not a constrainingmember, an internal constraining member is present. The deformation ofthe elastically deformable stem can be controlled by moving the elasticmember between a first position wherein the elastic member is linearlyconstrained, and a second position wherein the elastic member issubstantially unconstrained. Alternately, the deformation of theelastically deformable stem can be controlled by moving the constrainingmember between a first position wherein the elastic member is linearlyconstrained, and a second position wherein the elastic member issubstantially unconstrained. Between the first, constrained, positionand the second, unconstrained, position, is a range of partial orvariable deployment.

The elastic member is formed of an elastic material, preferably apseudoelastic material such as a shape memory alloy, which is capable ofbeing greatly deformed without permanent deformation. This provides animproved instrument that can be used in applications in which there is alimited amount of space. The instrument can be operated remotely, and atangles to the line of insertion, more conveniently than previousinstruments. The instrument, with appropriately configured blade edgesand/or tips, can be used to grasp, cut, and/or dissect tissue.

A remotely operated instrument of this invention comprises (a) a bladedelement having a first pivoted blade, and a second opposing blade; (b)an elastically deformable stem connected to the bladed element, theelastically deformable stem including an elastic member; (c) aconstraining member which can constrain the elastic member in asubstantially linear configuration; (d) a blade actuator means forcontrolling pivotal motion of the pivotable blade(s); and (e) a stemdeforming means for controlling deformation of the elasticallydeformable stem. A separate blade rotator means, for controllingrotation of the plane through which the blade(s) are pivoted, ispreferably included.

An alternate remotely operated instrument of this invention comprises:(a) a bladed element, having opposable blades including a first bladewhich is mounted for movement relative to the second blade; the firstblade being moveable between a closed position wherein the axes of theblades are substantially parallel, and an open position, wherein theaxes of the blades are deflected from the parallel; (b) an elasticallydeformable stem including an elastic member which is substantiallynon-linear in its unconstrained shape; (c) a constraining member whichconstrains the elastic member in a substantially linear shape; (d) ablade actuator means, said blade actuator means controlling position ofthe opposing blades between the open position and the closed position;and (e) a stem deformation controlling means. A rotation means, forcontrolling the plane of the blades, is preferably included.

The elastically deformable stem includes at least one elastic memberwhich assumes a linear configuration when constrained, and which iscurved when unconstrained. The elastic member is held in a constrainedconfiguration by the presence of the constraining member. Elasticmaterials which are suitable for use in the elastic member includepseudoelastic and superelastic materials, as described below.

When an elongate housing is present and acts as the constraining member,the instrument is moveable between a first position wherein theelastically deformable stem and, optionally, the bladed element, are arewithin the housing, and a second position wherein the bladed element andat least part of the elastically deformable stem are deployed from thehousing. The elastically deployable stem includes an elastic memberwhich is curved at a predetermined angle with respect to the elongatehousing when the elastically deformable stem is deployed from thehousing. When the housing acts as the constraining member, varying theamount of deployment of the elastically deformable stem varies the angleof presentation of the bladed element.

In an alternate embodiment, the elastic member is constrained in alinear configuration by the action of an internal constraining member,such as an internal constraining rod. Movement of the internalconstraining member relative to the elastic member causes variabledeformation of the elastically deformable stem. An elongate housing mayor may not be present in embodiments in which an internal constrainingmember is present.

The bladed instrument can comprise a grasping device (e.g., a forceps),a cutting device (e.g., a scissors), or a dissecting device.

A surgical instrument of this invention consists essentially of: abladed element having opposable blades, at least one of which ispivotally mounted for movement; a blade actuator means for causingpivotal motion of the pivotable blade(s); an elastically deformable stemconnected to the bladed element; and a variable constraining means forcausing deformation of the elastically deformable stem.

The instrument is particularly useful in applications in which access toan object to be cut, grasped, or dissected is restricted. For example,the instrument is especially useful in medical applications in which theobject to be cut, grasped, or dissected is part of a human or animalbody. In such applications, the surgical instrument generally includesor is passed through a sheath in the form of a cannula, catheter, orendoscope. The distal end of the sheath is introduced through an openinginto a body cavity, duct, or joint, for example during laparoscopicsurgery.

The instrument may also be useful in the assembly of mechanical,electrical or other equipment, especially when access to the worksite islimited, or when the worksite is located at an angle to the access.

The instrument includes an elastically deformable stem, so that thebladed element can be variably angled away from the angle ofintroduction. When an elongate housing (e.g., a sheath) is present, thebladed elements can be arranged such that the axis on which the elementscut, grasp, and/or dissect the object is not coaxial with the axis of atleast a significant portion of the elongate housing.

The elastically deformable stem includes at least one elastic member,which is made of an elastic material. The elastic member is manufacturedin a non-linear shape. For example, the elastic member is manufacturedhaving one or more (generally one) bend, curve or twist. The bend, curveor twist can describe any desired angle. The angle described by theelastic member is generally less than 270°, more generally less thanabout 180°. For many applications, an angle of about 90° is preferred.The angle described by the elastic member in its unconstrained shape isthe maximum amount of deformation which can be attained by theelastically deformable stem.

The elastic member is deformed (constrained) from the bent configurationtowards the straight configuration, and held in the straight(constrained) configuration during positioning of the instrument.Preferably, the bladed element is fully functional when the blades arenot housed within the elongate housing, whether or not the elasticallydeformable stem has been deployed. When the elastically deformable stemis to assume an angled (unconstrained) configuration, the constrainingmember is removed. When the elastically deformable stem is constrainedby an elongate housing, the housing is withdrawn to permit the elasticmember to regain its bent (unconstrained) shape, and thus deform theelastically deformable stem. When the elastically deformable stem isconstrained by a constraining rod, for example, the rod is preferablywithdrawn to permit the elastically deformable stem to regain its bent(unconstrained) shape. Alternately, the elastic member can be deployedbeyond the constraining member to permit the elastic member to assumeits unconstrained shape and to deform the elastically deformable stem.

The amount of deformation of the elastically deformable stem can bevariably controlled between the maximum and the minimum by manipulationof the constraining member. The constraining means is generally alongitudinally slidable rigid member. The constraining member cancomprise, for example, a stiff elongate housing, or a substantiallylinear stiff constraining rod. Alternatively, the constraining membercan be fixed, and the elastic member can be slidable relative to theconstraining member.

The elastically deformable stem can be, for example, a rod, one or morewires, a hollow tubular element, or the like.

When the instrument includes a housing which acts to constrain theelastic member into a substantially linear shape, the housing and theelastically deformable stem are moved longitudinally relative to eachother to release the elastic member from lateral constraint. The elasticmember regains its original (unconstrained) non-linear shape, and thusto deform the elastically deformable stem. This approach is shown ingraphic cross-section in FIG. 7-3.

Alternatively, the elastically deformable stem can include asubstantially linear constraining rod. This constraining rod deforms theelastic member into a substantially linear shape. As the constrainingrod and the elastic member are withdrawn relative to one another, theelastic member regains its original non-linear shape and causes theelastically deformable stem to deform. This approach is shown in graphiccross-section in FIG. 7-4.

In yet another embodiment (not shown), the instrument includes asubstantially linear constraining moans which has a fixed position. Thisconstraining means deforms the elastic member into a substantiallylinear shape. As the elastic member and the constraining rod arewithdrawn relative to one another, the elastic member regains itsoriginal non-linear shape and causes the elastically deformable stem todeform.

The elastic member of the elastically deformable stem comprises anelastic material which is substantially linear in its constrainedconfiguration, and is curved in its unconstrained, or "memory",configuration. The term "elastic material" is used herein to mean amaterial that has spring-like properties, that is, it is capable ofbeing deformed by an applied stress and then springing back, orrecovering, to or toward its original unstressed shape or configurationwhen the stress is removed. The elastic material is preferably highlyelastic. The material can be polymeric or metallic, or a combination ofboth. The use of metals, such as shape memory alloys, is preferred.Shape memory alloys that exhibit pseudoelasticity, in particularsuperelasticity, are especially preferred. The elastic materials hereinexhibit greater than 1% elastic deformation, more generally greater than2% elastic deformation. Preferably, the elastic materials herein exhibitgreater than 4% elastic deformation, more preferably greater than 6%elastic deformation.

Preferably, the elastic member is at least partially formed from apseudoelastic material, such as a shape memory alloy.

The Figures are drawn for clarity and are not drawn to scale.

FIG. 7-1 shows a bladed instrument of this invention. As shown, ascissors-type blade actuator mechanism 110 controls the pivotal movementof the blades 112. A finger-activated stem deformation controlling means114 is used to control the deployment of the bladed element 116 and theelastically deformable stem 118 from the elongate housing 120. A rotatormechanism 122 is shown in the form of a knob, and is used to rotate theelastically deformable stem 118 and the bladed element 116 around thelong axis of the elongate housing β. Each of the actuator mechanism 110,the stem deformation controlling means 114, and the rotator mechanism122 can take any suitable manually operated configuration. The specificconfiguration of each of the actuator mechanism 110, the stemdeformation controlling means 114, and the rotator mechanism 122 can bethe same, or they can be different, as shown. Examples of suitablemanually operated mechanisms include one or more slider, pistol griphandle, scissors handle, and/or plunger arrangement. These and othersuch devices are well known to the art.

An elongate housing 120 maintains the elastic member 124 in asubstantially linear configuration prior to deployment of theelastically deformable stem 118 and the bladed element 116. Upon fulldeployment from the elongate housing, the bladed element 116 assumes aposition which is at an angle from the elongate housing 120. It shouldbe noted that the angle φ between the elongate housing 120 and thebladed element 116 can be any number of degrees desired. As shown, angleφ is approximately 60°. Angle φ is defined by the axis of the elongatehousing β, and the plane which is perpendicular to the axis of the pivot126 around which the blades pivot. Angle φ can be any desired angle.Preferably a rotator mechanism 122 is provided, and permits rotation ofthe bladed element 116 and the elastically deformable stem 118 aroundthe long axis of the elongate housing β. The rotation of the bladedelement 116 is preferably independent of the amount of deployment of theelastically deformable stem 118.

The elongate housing 120 is an elongate sheath having an axial bore (notshown) therethrough. The axial bore is sized to receive the elasticallydeformable stem and, optionally, the bladed element, in a constrainedconfiguration. The axial bore can have a consistent dimension throughthe length of the elongate housing 120, or the axial bore can widen andnarrow as necessary to conform to the shape of the elasticallydeformable stem 118 and, optionally, to the bladed element 116.

In general, the elongate housing 120 can be flexible or rigid, and therigidity can vary by region. When the elongate housing does not act asthe constraining member, an alternate constraining member (such as aninternal constraint) must be present. Standard catheters andlaparoscopic devices well known to the art are appropriate housings forthe bladed element and the elastically deformable stem. The stiff-sheathelongate housing of FIG. 7-1 can be polymeric or metallic, for examplestainless steel. A preferred stiff elongate housing is a rigid elongatetube of stainless steel.

The elongate housing 120 can be circular in cross-section, but othercross-sections may be preferable in some situations. For example,squared, oval, or eccentric cross-sections can be used. The elongatehousing can be substantially uniform in cross-section along its length,or it can vary.

The specific configuration and dimensions of the elongate housing 120will vary with the use of the device, the parameters of the bladedelement, and whether access for additional surgical devices is provided.The outer diameter of the elongate housing will vary with theapplication and the size of the bladed element. For example, theelongate housing in a laparoscopic device will have a diameter of fromless than about 3 mm to about 1.5 cm or greater; the length of alaparoscopic device will be from less than about 20 cm to about 30 cm orgreater.

In any of the embodiments of this invention, a suitable means may beprovided for passing a fluid (liquid or gas) through the device forirrigation, aspiration, insufflation, and the like. In any of theembodiments of this invention, electricity may be passed to one or bothend portion(s) of the blade(s) for purposes of electrocautery orelectrocutting.

FIGS. 7-2a through 7-2d are side views of the distal end of aninstrument of this invention. The instrument shown in FIG. 7-2 includesa rigid elongate housing 128 which acts as the constraining means.

As shown in FIG. 7-2, the instrument is moveable between a firstposition (FIG. 7-2a or FIG. 7-2b) wherein the elastically deformablestem 132 is constrained within the elongate housing 128, and a secondposition (FIG. 7-2d) wherein the bladed element 130 and the elasticallydeformable stem 132 extend past the constraint of the elongate housing128 and assume a memory shape. In one embodiment, both the elasticallydeformable stem 132 and the bladed element 130 are fully retractableinto the elongate housing 128, as shown in FIG. 7-2a. Between the firstposition and that shown in FIG. 7-2d are degrees of deployment (forexample that shown in FIG. 7-2b and FIG. 7-2c) in which the bladedelement 130 is deployed sufficiently for use (FIG. 7-2b), and in whichthe elastically deformable stem 132 is partially deployed (FIG. 7-2c).In an alternate embodiment, the bladed element 130 is not retractableinto the elongate housing 128. Such an embodiment is demonstrated inFIGS. 7-2b through 7-2d. These variable degrees of partial deploymentallow the operator to choose the angle of deflection that the bladedelement assumes relative to the elongate housing 128. (Pivotal actuationof the blades is not shown in this series of figures.)

After use, the instrument is removed from the worksite. When theworksite is within a patient, the elastically deformable stem 132 and,optionally, the bladed element 130, are retracted back into the elongatehousing 128 before the instrument is removed from the patient: thevarious elements therefore resume the configuration shown in FIG. 7-2abefore removal. If only the elastically deformable stem 132 is retractedback into the elongate housing 128 before the instrument is removed fromthe patient, the elements resume the configuration shown in FIG. 7-2bbefore removal.

FIG. 7-2b shows the blades 134 free of the elongate housing 128. Theblades 134, the pivot 136, and other elements necessary for pivotalmotion of one or more blade (but not including the blade actuator)comprise the bladed element 130. A portion of the elastic member 138 isshown. In the pictured embodiment, the elastic member-138 comprises twostrips of elastic material, each strip being secured to the pivot 136.The elastic member 138 can have any desired cross-sectional shape, andthe cross-sectional shape can vary along its length. Preferredcross-sectional shapes include a tubular shape or rod shape, and arectangular or roughly rectangular shape. In the embodiment shown theelastic member 138 comprises two strips which are not in the neutralplane of bending of the elastically deformable stem 132: this is a lesspreferred configuration. The preferred placement of the elastic memberis at or near the neutral plane of bending of the elastically deformablestem 132, and is discussed further below.

FIG. 7-2c shows the bladed element 130 as it is deployed axially fromthe elongate housing 128.-Also shown is a portion of the elastic member138. Shown next to the elastic member 138 is the blade actuator rod 140.In this embodiment, the elastic member 138 and the blade actuator rod140 are included within the elastically deformable stem 132. Theactuator rod 140 is preferably centrally located within the elasticallydeformable stem.

The blade actuator rod 140 can comprise a rod, strip, filament, cord,conduit, catheter, pipe, lever, or other suitable connecting means whichallows the remote pivotal manipulation of the blade(s). More than onesuch element can be present. The cross-sectional parameters of the bladeactuator rod can vary along its length. Any suitable material, includinga shape-memory material, can be used to form the blade actuator rod 140.In one embodiment, the elastic member also acts as the blade actuatorrod 140. The blade actuator rod 140 preferably has sufficientflexibility that it does not interfere with the elastic deformation ofthe elastic member 138. The blade actuator rod 140 can be positioned asdesired within the elastically deformable stem 132. Preferably, theblade actuator rod 140 is located in a position that does not interferewith the longitudinal motion of the elastic member 138 or of theconstraining member, and does not interfere with the bending motion ofthe elastic member 138. At the actuator end of the instrument (notshown), the blade actuator rod 140 can integrate with an actuator means,such as a slider mechanism, pistol grip or thumb actuated mechanism,scissors handle, and/or plunger mechanism. Alternatively, the actuatorrod 140 projects proximally from the elongate housing 128, and can bedirectly manipulated to cause pivotal motion of the opposing blades. Theblade actuator means includes the actuator rod 140, any apparatusnecessary to integrate with the bladed element, and the actuatormechanism (if any). The blade actuator means is used remotely to openand close the bladed element. Illustrative actuating means are describedmore fully below with reference to the drawings and include rack andpinion means, pin and slot means, four-bar linkages, and the like. Incertain embodiments, the actuating means may be formed of apseudoelastic material. The actuating means may permit the bladedelement to be axially rotated. The actuating means can also providesuitable means for irrigating or aspirating the workfield of the bladedelements, or can conduct electrical current to one or both of theblades, if desired.

FIG. 7-2d shows the bladed element 130 in the fully deployedconfiguration. The elastically deformable stem 132 is fully deployed(i.e., has achieved its fully unconstrained shape), and, as depicted,holds the bladed element 130 in position approximately 90° from the axisof the body of the instrument.

Reconstraining the elastically deformable stem 132 as shown in FIG. 7-2dis accomplished by reversing the process, i.e., by moving the elementsto the configuration shown in FIGS. 7-2c, 7-2b, and (optionally) 7-2a,sequentially.

FIG. 7-3 provides cross-sectional views of one segment of an elasticallydeformable stem 142 in constrained (FIG. 7-3a), partially constrained(FIG. 7-3b), and unconstrained (FIG. 7-3c) configurations.

FIG. 7-3a shows a section of an elongate housing 144 which surrounds theelastically deformable stem 142. The elastically deformable stem 142 isfully constrained by the elongate housing 144, and is in a substantiallylinear configuration. The elastically deformable stem 142 includes anelastic member 146 in the shape of a a tube, and the enclosed bladeactuator rod 148.

The elongate housing 144 and the elastically deformable stem 142 arecapable of reciprocal longitudinal motion, e.g., are longitudinallyslidable relative to one another. For example, the elongate housing 144can be moved in direction L (arrow) to deploy the elastically deformablestem 142. The same effect can be achieved by moving the elasticallydeformable stem 142 in direction R (arrow). Alternatively, the elongatehousing 144 can be moved in direction L (arrow) while the elasticallydeformable stem 142 is moved in direction R (arrow), to achievedeployment of the elastically deformable stem 142. Point a is labeled onFIGS. 7-3a, 7-3b and 7-3c, and shows the relative movement of theelastically deformable stem 142 relative to the elongate housing 144.

FIG. 7-3b shows the section of elastically deformable stem 142 in apartially deployed configuration. The elastically deformable stem 142 ispartially constrained in a linear configuration by the elongate housing144, and partially unconstrained.

FIG. 7-3c shows the section of elastically deformable stem 142 in afully deployed configuration. The elastically deformable stem 142 isunconstrained, and shows the maximum deformation available from thespecific elastic member 146.

Reconstraining the elastically deformable stem 142 as shown in FIG. 7-3cis accomplished by reversing the process, i.e., by moving the elementsto the configuration shown in FIGS. 7-3b and 7-3a, sequentially.

FIG. 7-4 provides views of one segment of an elastically deployable stem150 in constrained (FIG. 7-4a), partially constrained (FIG. 7-4b), andunconstrained (FIG. 7-4c) configurations.

FIG. 7-4a shows a section of an elastically deformable stem 150 which isconstrained by the constraining rod 152, and is held in a substantiallylinear configuration. The elastically deformable stem 150 comprises anelastic member 154, the blade actuator rod 156, and the constraining rod152.

The constraining rod 152 and the elastically deformable stem 150 arelongitudinally slidable relative to one another. For example, theconstraining rod 152 can be moved in direction L (arrow) to causedeformation of the elastically deformable stem 150. The same effect canbe achieved by moving the elastically deformable stem 150 in direction R(arrow). Alternatively, the constraining rod 152 can be moved indirection L (arrow) while the elastically deformable stem 150 issimultaneously moved in direction R (arrow), to achieve deformation ofthe elastically deformable stem 150. Point b is labeled on FIGS. 7-4a,7-4b and 7-4c, and shows the relative movement of the elasticallydeformable stem 150 relative to the constraining rod 152.

FIG. 7-4b shows the section of elastically deformable stem 150 in apartially deployed configuration. The elastically deformable stem 150 ispartially constrained in a linear configuration by the constraining rod152, and partially unconstrained.

FIG. 7-4c shows the section of elastically deformable stem 150 in afully deployed configuration. The elastically deformable stem 150 isunconstrained, and shows the maximum deformation available from thespecific elastic member 154.

Reconstraining the elastically deformable stem 150 as shown in FIG. 7-4cis accomplished by reversing the process, i.e., by moving the elementsto the configuration shown in FIGS. 7-4b and 7-4a, sequentially.

In one embodiment (not shown) the elastically deformable stem and therigid constraining rod are present only at the distal (introduced) endof the instrument, near the bladed element. The major portion of theintroduced body of the instrument is relatively flexible. Such anembodiment finds particular use as an endoscopic device, i.e., a devicewhich can be introduced through naturally occurring openings. In thehuman body, endoscopic devices are appropriate for use in therespiratory tract introduced through the mouth or nose),gastrointestinal tract (introduced through the mouth, nose, or rectum),or in the urogenital tract (introduced through the ureter or, in women,the vagina).

The material of the flexible housing of the endoscopic instrument may bepolymeric. If made of a flexible polymeric material, the material may bereinforced, for example, with fibers. A suitable polymeric material forthe component is, for example, polytetrafluoroethylene, reinforced withbraided fibers.

The elongate housing in an endoscopic device will have a diameter offrom less than about 0.7 mm to about 4.5 cm or greater; the length ofendoscopic devices will be from less than about 10 cm to about 3 metersor greater.

FIGS. 7-5 through 7-7 each show a different embodiment of theelastically deformable stem of this invention.

FIG. 7-5a shows a portion of an elastically deformable stem 158 and ofan elongate housing 160. Shown in cutaway view are the blades 162 andthe pivot 164, sheathed within the elastically deformable stem 158. Inthe shown embodiment, the blades 162 must be deployed from the elasticmember 166 prior to pivotal blade movement, controlled by the bladeactuator rod 168. The plane through which the blades 162 open can be inany orientation desired relative to the elastically deformable stem 158or to the elongate housing 160.

FIG. 7-5b shows a cross-sectional view of the elastically deformablestem 158, taken through line 5b--5b of FIG. 7-5a. The blade actuator rod168 is fully enclosed by the elastic member 166.

FIG. 7-6a shows a portion of an elastically deformable stem 170 having arod-and-groove configuration, and of an elongate housing 172. The bladeactuator rod 174 is partially enclosed by the elastic member 176, and ispartially exposed.

FIG. 7-6a shows an embodiment wherein the blades 178 and the pivot 180are not substantially sheathed within the elastically deformable stem170 when the elastically deformable stem 170 is fully withdrawn into thehousing 172. The blades 178 do not need to be deployed from the elasticmember prior to pivotal blade movement, controlled by the blade actuatorrod 174. The plane through which the blades 178 open can be in anyorientation desired relative to the elastically deformable stem 170 orto the elongate housing 172.

FIG. 7-6b shows a cross-sectional view of the elastically deformablestem 170, taken through line 6b--6b of FIG. 7-6a. The blade actuator rod174 is partially enclosed in a groove in the elastic member 176.

FIG. 7-7a shows a portion of a housing 182, and an elasticallydeformable stem 184 with a windowed configuration. The windows are shownon the convex surface of the elastically deformable stem 184. Suchwindows can be present on any of the concave or lateral surfaces of theelastically deformable stem 184, as desired. Any number of windows canbe used, including one, two, or a multiplicity.

Shown in cutaway view are curved blades 190 and the pivot 192, which aresubstantially sheathed within the elastically deformable stem 184. Asshown, the blades 190 must be deployed prior to pivotal blade movement.When the blades 190 are curved, it is generally preferable that thecurve of the blades 190 continue the curve of the elastically deformablestem 184, but that is not necessary.

The plane through which the blades 190 open can be in any orientationdesired to the elastically deformable stem 184, or to the elongatehousing 182. In a currently preferred embodiment, the blades 190 are notretracted into the elongate housing 182 or into the elasticallydeformable stem 184 even when the blades are fully retracted, aconfiguration which is shown in FIG. 7-2b.

FIG. 7-7b shows a cross-sectional view of the elastically deformablestem 184, taken through line 7b--7b of FIG. 7-7a. The blade actuator rod186 is partially enclosed in a groove in the elastic member 188.

FIG. 7-7c shows a cross-sectional view of the elastically deformablestem 184, taken through line 7c--7c of FIG. 7-7a. The blade actuator rod186 is fully enclosed by the elastic member 188.

FIG. 7-8 demonstrates the use of an alternate elastic member 194. Asshown in FIG. 7-8a, the elastic member 194 is an element such as a wirewhich describes a closed shape in its unconstrained shape. The elasticmember 194 has a stem 196, which can be a continuation of the elasticmember 194, as shown, or can be a handle means connected to the elasticmember 194. Point g and point h are labeled to show the progression ofthe loop as it is withdrawn into the constraining housing 198. FIG. 7-8bdemonstrates that when the stem 196 and the elastic member 194 areretracted into a constraining housing 198, the circle deforms into acupped configuration. As shown in FIG. 7-8c, further retraction of thestem 196 and the elastic member 194 into the constraining housing 198causes further deformation. The closed shape becomes narrowed andsharply angled. This occurs because as the sides of the closed shapetake less stress to rotate out of the plane of the undeformed shape thanto straighten within the plane of the undeformed shape. The figure thusdeforms by bending at the apex, with the sides rotating out of the planeof the undeformed shape rather than.

FIGS. 7-8d, 7-8e and 7-8f show the incorporation of the closed shape ofFIGS. 7-8a, 7-8b and 7-8c, respectively, into an enclosing flexiblesheath 200. FIGS. 7-8d, 7-8e and 7-8f are side views of the flexiblesheath 200 and constraining housing 198 which show the bending whichtakes place as the stem (not shown) and the circular elastic member (notshown) are drawn into the constraining housing 198.

FIG. 7-9 demonstrates another method of constraining an elastic member.FIG. 7-9a shows two unconstrained elastic members 202a and 202b. Each iscurved when it is not constrained. Each is capable of independentrotation. As shown in FIG. 7-9a, the elastic members 202a and 202b areangled away from each other.

FIG. 7-9b shows the elastic members 202a and 202b held within a flexiblesheath 204. The sheath causes each elastic member to act as a constraintfor the elastic member having an opposite bend. As a result, theflexible sheath 204 is straight.

FIG. 7-9c shows the elastic members 202a and 202b held within a flexiblesheath 204. Elastic member 202b has been rotated to align its curve tothe curve of elastic member 202a. The sheath bends to conform to thebend of the two elastic members 202a and 202b.

FIGS. 7-9d through 7-9f graphically represent the forces involved inFIGS. 9a through 9c, respectively, as represented in top view.

FIG. 7-9d depicts vectors for the elastic members 202a and 202b, asshown in FIG. 7-9a. Elastic member 202a is shown as a vector arrowpointing to the left; elastic member 202b is shown as a vector arrowpointing to the right.

FIG. 7-9e depicts vectors for the elastic members 202a and 202b as shownin FIG. 7-9b. The flexible sheath 204 is shown. The flexible sheath 204does not curve, as the forces exerted by the elastic member 202a arecancelled out by the forces exerted by elastic member 202b.

FIG. 7-9f depicts vectors for the elastic members 202a and 202b, asshown in FIG. 7-9c. The flexible sheath 204 is shown. The flexiblesheath 204 curves to the left, represented by the resultant arrow 205.The vector forces exerted by the elastic member 202a are reinforced bythe vector forces exerted by elastic member 202b.

FIG. 7-9g depicts alternate vectors for elastic members 202a and 202b.The flexible sheath 204 is shown. Elastic member 202a is represented bya vector leftward, while elastic member 202b is represented by a vectorwhich is at a 90° angle from that of elastic member 202a. The forcesexerted by the elastic member 202a are only partially reinforced by theforces exerted by elastic member 202b. The flexible sheath 204 curves tothe upper left, represented by the resultant arrow 206.

FIG. 7-9h depicts another vector set for elastic members 202a and 202b.The flexible sheath 204 is shown. Elastic member 202a is represented bya vector downward, while elastic member 202b is represented by a vectorto the right. The forces exerted by the elastic member 202a are onlypartially reinforced by the forces exerted by elastic member 202b. Theflexible sheath 204 curves to the lower right, represented by theresultant arrow 207.

FIG. 7-9i depicts yet another vector set for elastic members 202a and202b. The flexible sheath 204 is shown. Elastic member 202a isrepresented by a vector downward, as is elastic member 202b. The forcesexerted by the elastic member 202a are reinforced by the forces exertedby elastic member 202b. The flexible sheath 204 curves to the bottom,represented by the resultant arrow 208. By rotation of one or more ofthe elastic members 202a and 202b, the flexible sheath 204 can be curvedthrough a 360° circle.

FIG. 7-10 shows a device of this invention having two pivoted blades,each blade having a longitudinal slot next to the pivot.

FIG. 7-10a is a side view of an instrument in the unconstrainedconfiguration with a partial cutaway near the bladed element. A bend ofapproximately 90° is present in the elastically deformable stem 210. Theactuating rod 212 is enclosed within the elastic member 214. Themovement of the actuating rod 212 and of the elastically deformable stem210 are preferably independent, and each is controlled by longitudinalmotion of the proximal ends. Opening and closing of the blades is causedby reciprocal motion of the proximal portion of the actuating rod 216.Deflection of the elastically deformable stem 210 is caused byreciprocal motion relative to the elongate housing 220 of the proximalportion of the elastically deformable stem 218.

FIG. 7-10b shows a cut-away top view of the instrument of FIG. 7-10a.Two blades 222a and 222b are present. As shown, each blade is V-shaped.In a preferred embodiment, not shown, each blade is substantiallystraight. A pivot 224 is present intermediate to the ends of the blade.The pivot allows pivotal motion of the two blades, and holds the bladesin position on the elastically deformable stem. A longitudinal slot 226is present in each blade proximal to the pivot. The two blades 222a and222b are moveable between a closed position, wherein the axes of thedistal portions of the blades are substantially parallel, and an openposition, wherein the axes of the distal portions of the blades aredeflected from the parallel. Pivotal movement of the blades 222 iscaused by a sliding pin (not shown) which is part of the actuator rod212, and which integrates with the longitudinal slot 226 present in eachof the blades. In alternate embodiments, the blades can be locatedpartially within the elastically deformable stem; the blades can befixed to opposite sides of the elastically deformable stem; or theblades can be fixed to a concave, convex, or lateral edge of theelastically deformable stem. The pivotal connection shown is fordemonstration purposes only, and any appropriate toggle, gear, orpivotal connection can be used.

FIG. 7-11a shows a longitudinal cross-sectional view of an instrument inthe unconstrained configuration. The bladed element 228 includes twoblades, two bars, and four pivots. A bend of approximately 90° ispresent in the elastically deformable stem 230. The actuating rod 232 isenclosed within the elastic member 234. The movement of the actuatingrod 232 and of the elastically deformable stem 230 are each controlledby longitudinal motion of the proximal ends. Opening and closing of theblades is caused by reciprocal motion of the proximal portion of theactuating rod 236. Deflection of the elastically deformable stem 230 iscaused by reciprocal motion of the proximal portion of the elasticallydeformable stem 238 relative to the elongate housing 240.

FIG. 7-11b and 7-11c show cut-away top views of the instrument of FIG.7-11a. Two blades 242a and 242b are present. Two bars 244a and 244b arepresent. A pivot 246a is present intermediate to the ends of the blades242a and 242b, joining the blades and attaching the blades to theelastically deformable stem 230. Two pivots 246b are present at theproximal ends of the blades 242a and 242b, where they join the distalends of bars 244a and 244b. A pivot 246c is present at the proximal endof the bars 244a and 244b, joining the bars. Pivotal movement of theblades 242a and 242b is caused by a sliding motion of the bladeactuating rod 232. FIG. 7-11b shows the blades in a relatively closedconfiguration. FIG. 7-11c shows the blades in a relatively openconfiguration.

FIGS. 7-12a through 7-12f show alternate cross-sections of anelastically deformable stem of the instrument of FIG. 7-1, taken throughline 12-12.

FIG. 7-12a shows an elastic member 248 and a blade actuator rod 250within a flexible material 252. The flexible material 252 describes asquared pyramid shape in cross-section. The elastic member 248 and theblade actuator rod 250 each comprise a strip of material which isroughly oval in cross-section.

The use of a flexible material 252 which encloses an elastic member 248and a blade actuator rod 250 permits the easy use of one or more elasticmember 248 and/or blade actuator rod 250 members which is eccentricallyshaped in cross-section. Additionally, the material of the flexiblematerial 252 is generally less expensive and easier to work than thematerial of either the elastic member 248 or the blade actuator rod 250.The flexible material 252 can be, for example, a flexible polymer, or abraided, coiled, segmented, hinged, or zigzagged metal component. Ifmade of a flexible polymeric material, the material may be reinforced,for example, with fibers, to enable it to withstand the forces exertedon it by the elastic member while it is constrained within and deformedby the elongate housing. A suitable polymeric material for the componentis, for example, polytetrafluoroethylene, optionally reinforced withbraided fibers.

The preferred cross-sectional embodiments include the actuator rod in orclose to the neutral plane, i.e., that plane which is neither compressednor stretched during the bending of the elastically deformable stem.FIGS. 7-12a through 7-12f are each labeled with a plane z--z,representing a preferred neutral plane; and with a plane n--n,representing a preferred plane through which the elastically deformablestem bends.

FIG. 7-12b shows two elastic members 248 on either side of an actuatorrod 250, within a flexible material 252. The flexible material 252 is arounded rectangle in cross-section. The elastic members 248 are rodswhich are round in cross-section, and the blade actuator rod 250comprises a strip of material which is oval in cross-section.

FIG. 7-12c shows two elastic members 248 on either side of an actuatorrod 250, within a flexible material 252. The flexible material 252 hasan oval cross-section. The elastic members 248 are square incross-section. The blade actuator rod 250 is a rod which is round incross-section.

FIG. 7-12d shows two elastic members 248 on either side of an actuatorrod 250, within a flexible material 252. The flexible material 252 hasan oval cross-section. The elastic members 248 are square incross-section. The blade actuator rod 250 is a piece which resembles arounded "H" in cross-section. In an alternate embodiment, not shown, theblade actuator rod includes a third elastic member within it, and theblade actuator rod slides freely along the third elastic member. Inanother embodiment, not shown, the elastic members and the actuator rodare held in position without the action of a flexible material. In yetanother embodiment, the elastic member is intermediate to two bladeactuator rods.

FIG. 7-12e shows an elastic member 248 and a blade actuator rod 250within a flexible material 252. The flexible material 252 has a squaredpyramid shape in cross-section. The elastic member 248 comprises a stripof material which is rectangular in cross-section. The blade actuatorrod 250 comprises a strip of material which is round in cross-section.

FIG. 7-12f shows an elastic member 248, a constraining rod 254, and anactuator rod 250, within a flexible material 252. The flexible material252 has a squared cross-section. The elastic member 248, theconstraining rod 254, and the actuator rod 250 are each oval incross-section. Note that the constraining rod is not within the neutralaxis: only in the absence of the constraining rod does the elasticmember 248 assume its unconstrained (bent) configuration. Aconfiguration such as that shown in FIG. 7-7f can be used in embodimentswhich do not include an elongate housing. A lumen 255 is present. Thelumen 255 can be used, for example, to provide access for one or moreapparatus for irrigation, aspiration, cautery, and the like.

FIG. 7-13 shows a bladed element in which only one pivoting blade 256 ismounted for pivotal motion. The pivoting blade 256 is biased in the open(splayed) position by a spring 258. The fixed blade 260 is mounted in afixed position. The pivoting blade is closed by longitudinal motion ofthe actuator rod 262. The housing 264 is shown in partial cutaway view.

Preferred embodiments of this invention include a symmetrical bladeaction, so that both of the blades are actuated by the manually operatedmechanism and dissection, cutting, and/or grasping is done bysymmetrical motion of the two blades. However, in some situations, itmay be desirable to have embodiments in which one blade is moved more bythe manually operated mechanism than the other blade. In some cases, itmay be desirable to have one blade function as a stationary (andtherefore passive) blade, where the manually operated mechanism movesonly the other blade.

The blades of this invention can be made of any appropriate material.Metals known for scissor, knife, and/or forceps use are appropriate.Stainless steel, for example, can be used. Rigid plastics can also beused.

One use of the instruments of this invention involves cutting, e.g, whenone or more of the opposable blade provides a cutting edge. The honingof an edge to form a cutting blade is well known in the art. If desired,the cutting blade can be serrated. The cutting edge is preferablyderived from beveling blade material itself. However, it may bedesirable or necessary to provide a honed edge of a secondary materialto the blade material. For example, a non-cutting plastic blade can becombined with an alloy cutting edge. A cutting surface can be providedat any desired exposed edge of the blade.

The blades can be straight, or they can be curved along their length, asshown in FIG. 7-7a. When curved blades are present, the curved bladesare preferably made of an elastic material as described above.

FIG. 7-13b shows a cutting blade 266 which has one longitudinal cuttingedge 268.

FIG. 7-13c shows cutting blade 266 in which the perimeter of the bladeprovides the cutting edge 268.

FIG. 7-13d shows a blade 266 which has no cutting edges. The end portionof the blade is pointed to facilitate dissection of tissues.

FIG. 7-13e shows a blade 266 which has no cutting edges. The end portionof the blade is curved.

FIGS. 7-14a through 7-14e show various blade cross-sections, takenthrough line 14--14 of FIG. 7-13a. The cutting surfaces of the bladesmay abut one another in the manner of wire cutters, or they may crossone another in the manner of shears. The grasping surfaces of the bladesmay abut one another and be sufficiently blunt to avoid cutting theobject to be grasped. Alternatively, the grasping surfaces need not beconfigured so as to contact each other in the manner of cutting devices.The object being grasped need merely be entrapped between the endportions of the blades. The grasping surfaces may be ridged or containprotuberances to assist in grasping the object.

FIG. 7-14a shows a cross-sectional view of two opposing blades. Theblades are roughly rectangular in cross-section: The blades meet at aflattened surface, and are appropriate for grasping objects.

FIG. 7-14b shows a cross-sectional view of two opposing ridged blades.The blades are roughly rectangular in cross-section. The blades meet ata ridged surface, and are especially appropriate for grasping objects.

FIG. 7-14c shows a cross-sectional view of two opposing blades in whichthe blades are not symmetrical. One blade is roughly rectangular incross-section, while the other blade is triangular. Such a configurationis appropriate for cutting objects.

FIG. 7-14d shows a cross-sectional view of two opposing cutting blades.The blades are roughly triangular in cross-section. The blades meet at apointed cutting surface.

FIG. 7-14e shows a cross-sectional view of two opposing cutting blades.The blades are roughly triangular in cross-section. The blades meet andslide along their surfaces in the manner of shears.

While the invention has been described in connection with specificembodiments thereof, those skilled in the art will recognize thatvarious modifications are possible within the principles describedherein. Such modifications, variations, uses, or adaptations of theinvention, including such departures from the present disclosure as comewithin known or customary practice in the art, fall within the scope ofthe invention and of the appended claims.

We claim:
 1. A surgical apparatus for manipulating matter at an intendedmanipulation temperature in a confined or inaccessible space,comprising:(i) manipulator means at least partly constructed of anelongate shape memory alloy member, said shape memory alloy memberhaving a distal end, said shape memory alloy member having two arms atsaid distal end thereof, said two arms having tips that approach but arenot fixed to one another, said shape memory alloy member havingpseudoelasticity at the intended manipulation temperature, and (ii) abarrier member spanning said two arms; (iii) a hollow cannula initiallyholding the shape memory alloy member in a relatively straightenedstate, and (iv) actuating means for extending the shape memory alloymember with said barrier member from the housing to manipulate matterwithin said space and for withdrawing the shape memory alloy member intothe housing, the arrangement being such that the shape memory alloymember bends or twists pseudoelastically in a lateral or helical senseto manipulate the matter on extending from the housing at saidmanipulation temperature, and the shape memory alloy member becomesrelatively straightened on withdrawal into the housing at saidtemperature.
 2. A device or apparatus according to claim 1 which is ofelongate form for surgical manipulation of matter within a living body,and which has the manipulator means at its distal end with the shapememory alloy member(s) having pseudoelasticity at the temperature to beencountered within that body, and wherein the actuating means isoperable from the proximal end of the device.
 3. Apparatus according toclaim 1 wherein said shape memory alloy member is disposed within saidcannula oriented such that said manipulator means exits said cannula ina predetermined lateral orientation; and the apparatus further comprisesmeans for indicating said predetermined lateral orientation. 4.Apparatus according to claim 3, further comprising means for preventingsaid manipulator means from rotating within said cannula.
 5. Anapparatus according to claim 1 wherein the shape memory alloy member, issuperelastic under the intended conditions of use.
 6. An apparatusaccording to claim 1, wherein the shape memory alloy member is composedof nickel-titanium shape memory alloy.
 7. An apparatus according toclaim 6 wherein the nickel-titanium shape memory alloy is capable ofmore than 4% elastic deformation.
 8. An apparatus according to claim 1,wherein the shape memory alloy member assumes a first shape in asubstantially austenitic phase when extended from the cannula, andassumes a second shape containing more martensitic phase when withdrawninto the cannula.
 9. An apparatus according to claim 1 wherein thebarrier member is sealable.
 10. An apparatus according to claim 1wherein said manipulator means is at least partly constructed of a bentor twisted elongate shape memory alloy member.
 11. An apparatusaccording to claim 1, further comprising a drawstring for sealing thebarrier member.
 12. An apparatus according to claim 11 wherein thenickel-titanium shape memory alloy is capable of more than 1.5% elasticdeformation.
 13. A surgical device comprising:(a) a housing; (b) anelastically deformable loop formed at least partially from a shapememory alloy wire and a barrier member disposed thereon, wherein saidloop comprises two arms, each arm having a distal end and a proximalend, which distal ends approach, but are not fixed to each other; and(c) means for reversibly moving the arms between a first positionwherein they are constrained within the housing, and a second positionwherein the arms are unconstrained by the housing and assume an expandedmemory shape, said proximal ends being attached to said means for movinganal said means being capable of withdrawing said arms into the housingindependently of the barrier member.
 14. A device according to claim 13,wherein said means for moving comprises a drawstring.
 15. A deviceaccording to claim 14, wherein the housing and the loop can be separatedfrom the barrier member and drawstring means in use.
 16. A deviceaccording to claim 13 including means for indicating the orientation ofthe elastically deformable loop when extended from the housing.
 17. Adevice according to claim 13, including means for preventing elasticallydeformable loop from rotating within the housing or cannula.
 18. Anapparatus according to claim 13, wherein the deformable loop is composedof nickel-titanium shape memory alloy.
 19. An apparatus according toclaim 18 wherein the nickel-titanium shape memory alloy is capable ofmore than 4% elastic deformation.
 20. A remotely operated surgicaldevice comprising:(a) an elongate housing; (b) a retractor, theretractor comprising a deformable loop comprising two finger-shapedmembers, wherein a membrane spans an area between said two finger-shapedmembers; and (c) means for projecting and retracting the retractorrelative to the housing between a first position wherein the retractoris constrained within the housing, and a second position wherein theretractor is unconstrained by the housing and assumes an expanded memoryshape.
 21. A device according to claim 20 which comprises an endoscopicdevice, a catheter, or a laparoscopic device.